Question

Tom knows that, in his school. 10 out of every 85 students are left-handed. There are 391 students in Tom's school. How many students in Tom's school are left handed.

Answer 1

10 out of 85 is the ratio of the left handed students in his school. There are only 391 students in toms school, and we are trying to figure out the proportional value of left handed people in his school. Let's start by figuring out the value of this solution. X (is the number of left handed Students we don't know.) the 10 And X are together side by side Becuase the Both don't give any further information added. We only know that 85 students are left handed also, but it's more of a ratio quantity of an amount...but you want to still put 391 and 85 together side by side cause they both work hand in hand with the number of students. (Sorry can't put the whole solution down it didn't work. ) Let's work this out by cross multiplying 391 and 10. Whenever you cross multiply two numbers together eventually you are gonna multiply. So when you multiply those two together it equals 3910, now we take the 3910 and divide it by 85 becuase we are still trying to firgure out X. The number of left handed students now resembles 46. :) that is your answer. So X = 46

Answer 2

If your information is for a percentage out of every 85, you need the total number divided by the 85:

391 students / out of 85
= 391 / 85
= 4.6

But in every 85, (of which there are 4.6), 10 of them are left handed (not 4.6 of them)

So multiply the 4.6 by the ten left handed students:

4.6 x 10
= 46

Therefore there are 46 left handed students in Tom's school