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Current time:0:00Total duration:3:04

Video transcript

Pedro is supposed to practice piano for 3/4 of an hour every day today he is practice for 1/4 of an hour what fraction of an hour does he need to practice so let's visualize 3/4 so he needs to practice 3/4 of an hour's so if this represents an entire hour so this represents an entire hour so let's divide it into fourths so now divided into halves now let's make it into 4 equal section now it's in 2/4 so he needs to practice so he needs to practice 3/4 of an hour so he needs to practice 3/4 of an hour that was my attempt at drawing an arrow so let me shade it in so he needs to practice he needs to practice 3/4 of an hour this gets us to 3/4 3/4 right over here so he needs to practice 3 out of the fourth of an hour so this is 3/4 now it says he is already practiced for 1/4 of an hour so he's already practiced for 1/4 1/4 so how much more does he need to practice how much more does he need to practice well he needs to practice this much more he needs to practice this much more than you might already see the answer visually but let's think about how to represent it as a as a fraction expression so let me write it like this so this is how much he needs to go how much how much does he need to practice so he needs to do a total of 3/4 he's already done 1/4 he's already done 1/4 so if you subtract 1/4 from the 3/4 you're going to get this amount right over here you're going to have to get you're going to get the amount that he needs to practice now this already has the same denominator so this is going to be equal to 3 minus 1 over 4 3 minus 1 over 4 which is equal to 2/4 and you see that right over there he still needs to practice 1 & 2 out of the fourths 2/4 now 2/4 we know is the same thing as 1/2 there's a couple of ways to think about it you could say hey look this is half of the length of this entire thing as a little bit on this end and that end or if you made if you made four blocks like this if you make four blocks if you make four equal blocks and if you were to shade in two of them you see that you have shaded in one half of the blocks this is the exact same amount as if I just divided into two sections and I shade it in only one of them to force is equal to one is the same thing as one half and if you wanted to work it out mathematically you just have to do the same thing to the numerator and the denominator so let's divide the numerator and the denominator by two because they are both divisible by two that's actually their greatest common factor so two divided by two is one four divided by two is two so what fraction of an hour does he need to practice he's got to practice half an hour