Pratica di Shadowing: Adding Fractions With Unlike Denominators - Impara a parlare inglese con i video

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In this video, we're going to talk about how to add two fractions.
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So let's start with this example.
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2 over 3 plus 3 over 4.
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So how can we add these two fractions?
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The first thing you can do is multiply the denominators of the fractions.
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3 times 4 is 12. And then cross multiply.
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2 times 4 is 8, and then multiply 3 times 3, and that will give you 9.
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And then you could add 8 and 9.
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8 plus 9 is 17.
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So we get the answer 17 over 12.
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And so this is our answer as an improper fraction.
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Now, let's try another example.
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So let's add 5 over 3 plus 1 over 2.
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So let's follow the same technique.
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3 times 2 is 6. And then cross multiply.
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5 times 2 is 10.
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3 times 1 is 3.
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And then we're going to add 10 plus 3.
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So 10 plus 3 is 13.
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So the answer is 13 over 6. by the way
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if you want more videos on fractions let's say how to subtract fractions how to multiply
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or divide fractions check out the description section of this video i'm going to post some links there
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that you might find useful
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but now let's get back to this video let's work on another problem
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so now it's your turn go ahead and add the following fractions 2 over 5 plus 1 over 4
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And also try this example, 3 over 7 plus 5 over 9.
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Feel free to pause the video and try those examples.
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So let's start with the first one.
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So first we're going to multiply 5 and 4.
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5 times 4 is 20. And then cross multiply.
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2 times 4 is 8.
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5 times 1 is 5.
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And now we can add 8 plus 5 is 13.
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So the answer is 13 over 20.
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Now let's try the example below.
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So let's multiply 7 by 9.
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7 times 9 is 63. And then cross multiply.
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3 times 9 is 27.
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And 7 times 5 is 35.
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So now we'll need to add 27 and 35.
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So you can use a calculator or you can do it the old-fashioned way.
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Let's do it the old-fashioned way.
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5 plus 7 is 12, so we need to write the 2, carry over the 1.
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And then 3 plus 2 plus 1 is 6.
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So 27 plus 35 is 62.
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So the final answer for that example is 62 divided by 63.
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So at this point, you know how to add 2 fractions.
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But what if you need to add, let's say, 3 fractions?
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What should you do?
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So before we go into this example, I want to show you another example of adding 2 fractions but using a different method.
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So let's start with this problem, 3 over 8 plus 5 over 7.
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So let's begin by using the method that you're familiar with
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and then we'll use a new method to get the same answer.
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So what we did before is multiply the two denominators of the fractions.
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8 times 7 is 56.
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And then we would cross multiply.
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3 times 7 is 21.
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And 8 times 5 is 40.
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And then we would add 21 plus 40 is 61.
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So our answer for this example would be 61 over 56.
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Now here's another method which is useful if you're adding multiple fractions.
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So what you want to do is get a common denominator of 56.
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In order to do so, the fraction on the left you need to multiply the top and the bottom by 7.
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And for the fraction on the right, multiply the top and the bottom by 8.
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So this would give you a common denominator of 56.
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So 3 times 7 is 21, and 7 times 8 is 56.
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5 times 8 is 40, and on the bottom, 7 times 8 is 56.
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Now whenever you're adding two fractions, if the denominator is the same, then you're allowed to add the numerators of the two fractions.
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So 21 plus 40 is 61.
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And thus, we're going to get the same answer of 61 over 56.
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This technique works if you're adding, let's say, three fractions or even four fractions.
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Now, let's try this example.
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2 over 5 plus 3 over 4 plus 1 over 3.
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So the first thing we need to do is identify a common denominator that we need to get to.
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So we need to find the least common multiple of 5, 4, and 3.
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How can we do so?
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Well, a simple way is to multiply 5 times 4 times 3.
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You could use any common multiple.
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It doesn't really have to be the least common multiple.
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But if you could find the least common multiple, then it's going to be easier.
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But let's keep it simple.
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so 5 times 4 times 3
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5 times 4 is 20 20 times 3 is 60 so 60 is a common multiple of 5, 4, and 3 it might even be the least common multiple
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and I think it is so what I'm going to do now is take 60 and divide it by 5
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60 divided by 5 is 12 so therefore I'm going to multiply the second fraction, I mean the first fraction, by 12.
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So that will give me a common denominator of 60.
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Now 60 divided by 4 is 15.
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So I need to multiply the second fraction, the top and the bottom, by 15.
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Whatever you multiply the bottom of a fraction by, you need to do so also to the top.
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Now 60 divided by 3 is 20.
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So I'm going to multiply the third fraction by 20 over 20.
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12 times 2 is 24 and we know that 12 times 5 is 60.
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15 times 3 is 45 and 15 times 4 is 60.
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20 times 1 is 20.
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20 times 3 is 60.
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So notice that we have a common denominator of 60.
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So now all we need to do is add up the three numerators.
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So let's find a sum of 45, 24, and 20.
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5 plus 4 is 9.
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4 plus 2 plus 2 is 8.
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So 24 plus 45 plus 20 is 89.
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So our answer for this problem is 89 over 60.
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So that's how you can add three fractions together.
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Now let's try another example.
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So now it's your turn.
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Go ahead and add 1 over 4 plus 5 over 6 plus 1 over 2.
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So let's identify the least common multiple of 4, 6, and 2.
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Multiples of 6 are 6, 12, 18, 24, and so forth.
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Multiples of 4 are 4, 8, 12, 16, 20.
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Multiples of 2 are 2, 4, 6, 8, 10, 12, 14.
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So which of these are the least common multiple of 2, 4, and 6?
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Notice that 12 is the lowest common number or lowest common multiple of 2, 4, and 6.
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So therefore, 12 is the least common multiple.
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Now, 12 divided by 4 is 3.
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So I'm going to multiply this fraction by 3 over 3.
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And 12 divided by 6 is 2.
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So I'm going to multiply this second fraction by 2 over 2.
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And 12 divided by 2 is 6.
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So I'm going to multiply this fraction.
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Let's change that color. By 6 over 6.
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So I'm going to get 3 over 12 plus 2 times 5 is 10.
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2 times 6 is 12.
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and then 6 times 1 is 6, 6 times 2 is 12.
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So now we need to add.
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3 plus 10 is 13.
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13 plus 6 is 19.
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So the final answer is 19 over 12.
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So that is it for this video.
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Be sure to check out my next video on subtracting fractions.
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I'm going to post some links in the description section of this video, so feel free to take a look at that.
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Thank you.

Per chi è questo video?

Questo video è perfetto per chi vuole imparare l'inglese con YouTube e ha bisogno di praticare sia la matematica che la comprensione orale. Ideale per studenti di livello intermedio che vogliono migliorare la loro capacità di seguire esplicazioni in inglese, soprattutto su argomenti tecnici come le frazioni. Se il tuo obiettivo è pratica di conversazione in inglese e di capire come le idee sono organizzate in una lezione, questo contenuto è per te: combina apprendimento matematico con esercizi di ascolto e ripetizione.

Parole e espressioni da rubare

Nel video, ci sono alcune espressioni utili per le conversazioni o le lezioni in inglese. Ecco quelle più interessanti:

  • Cross multiply: "Moltiplicare incrociato" – usato per descrivere l'operazione tra frazioni. Esempio: "2 times 4 is 8, and then multiply 3 times 3" (2 per 4 fa 8, poi 3 per 3).
  • Improper fraction: "Frazione impropria" – una frazione dove il numeratore è maggiore del denominatore. Il video lo usa per definire "17 over 12".
  • Old-fashioned way: "Modo antico" – per indicare un metodo tradizionale, come fare l'addizione a mano. Esempio: "do it the old-fashioned way" (farlo a mano).

Come migliorare la pronuncia inglese con questo video

Per migliorare la pronuncia inglese, usa la tecnica del shadowspeaks (o shadow speak): ascolta una frase, pausa il video e ripeterla immediatamente, imitando l'intonazione e il ritmo dello speaker. Nota come le parole come "denominators" (denominatori) e "multiply" (moltiplicare) sono pronunciate con accento sulla seconda sillaba. Lo speaker usa una velocità media, perfetta per esercitarsi: cerca di seguire la sua fluidità, specialmente nelle frasi lunghe come "So 27 plus 35 is 62, so the final answer is 62 divided by 63". Ripeti più volte gli esempi pratici: la ripetizione aiuta a memorizzare non solo le parole, ma anche la struttura delle frasi in inglese.

Cos'è la tecnica dello Shadowing?

Shadowing è una tecnica di apprendimento delle lingue supportata da studi scientifici, originariamente sviluppata per la formazione dei traduttori professionisti e resa popolare dal poliglotta Dr. Alexander Arguelles. Il metodo è semplice ma potente: ascolti un audio in inglese di madrelingua e lo ripeti immediatamente ad alta voce — come un'ombra che segue il parlante con un ritardo di solo 1–2 secondi. A differenza dell'ascolto passivo o degli esercizi di grammatica, lo shadowing costringe il tuo cervello e i muscoli della bocca a elaborare e riprodurre simultaneamente i modelli di discorso reale. La ricerca dimostra che migliora significativamente la precisione della pronuncia, l'intonazione, il ritmo, il discorso connesso, la comprensione dell'ascolto e la fluidità del parlato — rendendolo uno dei metodi più efficaci per la preparazione alla prova di speaking dell'IELTS e per la comunicazione reale in inglese.

Tecnica dello shadowing: leggi la guida completa passo dopo passo →