4
There are 270 students in Year 7
Each student studies one of French or German or Spanish.
Of these 270 students
2
study French
9
the number who study French : the number who study Spanish = 3:7
42 boys study German
Of the students who study German, what percentage are boys?
You must show your working.

4 There are 270 students in Year 7 Each student studies one of French or German or Spanish Of these 270 students 2 study French 9 the number who study French th class=

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Answer is 60%

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so, for this one you first figure out how many study French.

2/9 of 270 is 60 (simple method: 1/9 is 270 divided by 9, which is 30. So 2/9 is 1/9 multiplied by 2, which is 60).
60 are doing French.

Then use this in the ratio of French to Spanish (3:7) and you have 3 and 60 on the same side. You have to multiply 3 by 20 to get to 60 (or divide 60 by 20 to get 3).
So the number you use to do the same to the other side of the ratio is 20.

7 multiplied by 20 (or 7 multiplied by 10, then multiply that by 2) to get 140.
140 are doing Spanish.

Then take the French and Spanish from the big total and you get 270-140-60=70
70 are doing German.

Of these 70, 42 are boys. 70-42 gives 28 girls. 42/70 is the fraction of boys doing German. This is the same as 6/10 and to get a percentage you multiply the fraction by 10 so that the bottom of it is out of 100 (so that’s 60/100).

And 60/100 is the same as 60%.

So your answer is 60%