Ratio And Proportion

The ratio of boys to girls in 5th year is 2:5 if there are 140 pupils in total, how many boys and girls are there?

b)if The ratio of boys to girls in 3rd year is 5:4 , how many girls would there be when there are 120 boys?

Respuesta :

1)
Data:

[tex] \frac{boys}{girls} = \frac{2}{5} [/tex]
Total pupils = 140

Solving:

[tex]140* \frac{2}{5} = \frac{280}{5} = 56boys[/tex]
[tex]140 - 56 = 84girls[/tex]


2)

Data:

[tex] \frac{boys}{girls} = \frac{5}{4} [/tex]
Total boys =120

[tex]g* \frac{5}{4} = 120[/tex]
[tex] \frac{5g}{4} = 120[/tex]
[tex]5g = 120*4[/tex]
[tex]5g = 480[/tex]
[tex]g = \frac{480}{5} [/tex]
g = 96

Answer: 96 girls