math may/june 2012 paper 1 question about ratios

[zainabkhann]

this may look easy for most of you guys but it is giving me alot of trouble help and explain in a good way please.

the ratio of boys to girls in a school is 3:4
There are 120 more girls than boys
How many students are in the school?

Will appreciate a good reply with thorough explanantion for me to understand.

Thanks

 

[aalmuhannadi]

this may look easy for most of you guys but it is giving me alot of trouble help and explain in a good way please.

the ratio of boys to girls in a school is 3:4
There are 120 more girls than boys
How many students are in the school?

Will appreciate a good reply with thorough explanantion for me to understand.

Thanks

The ratio of boys to girls is 3:4.
There are 120 more girls than boys. This means that 1 part must equal to 120, since the difference between 4 and 3 is 120.
So since 1 part is 120, multiply 120 by 3 and then multiply 120 by 4, and add the products of those two to get 840.

 

[zainabkhann]

The ratio of boys to girls is 3:4.
There are 120 more girls than boys. This means that 1 part must equal to 120, since the difference between 4 and 3 is 120.
So since 1 part is 120, multiply 120 by 3 and then multiply 120 by 4, and add the products of those two to get 840.

Oh alright thanks for the good explanation

 

[UbaidChawla]

480 girls and 360 boys = 840 students in the school