There are 3 boys for every 4 girls in school. If there are 200 girls, how many pupils are there in all? Help me please. This is my homework and I need it right now because we have a class for tomorrow.
Let the number of boys be 3x
let the number of girls be 4x
( notice 3x : 4x = 3 : 4 )
given : 4x = 200
x = 50
So we have 150 boys and 200 girls, for a total of 350.
( notice 150:200 = 3:4 , as required)
To solve this problem, we can use a ratio.
We know that there are 3 boys for every 4 girls. This means that the ratio of boys to girls is 3:4.
We are given that there are 200 girls. To find the number of boys, we can set up a proportion:
(3 boys) / (4 girls) = (x boys) / (200 girls)
Cross-multiplying, we get:
3 * 200 = 4 * x
600 = 4x
Dividing both sides by 4, we find that:
x = 150
Therefore, there are 150 boys.
To find the total number of pupils, we can add the number of boys and girls together:
Total pupils = Number of boys + Number of girls
Total pupils = 150 boys + 200 girls
Total pupils = 350
So, there are 350 pupils in total.