Expert: Paul Klarreich - 5/17/2008

Question
A High School had an enrolment of 1150 pupils. The ratio of boys to girls was 23:27.
a. How many boys were enrolled.
b.How many girls were enrolled.
Could you please help me with the working out of this     question.
Answer: a. 529 boys,
       b.  621 girls
Also
Population of a town has 38250 males and 30600 females.
a. what is the ratio of males to females
b.If 2000 males come to live in the town, how many extra females are needed to maintain the same ratio
Answer:a. 5:4
      b.1600 females

Thankyou for your help

Answer
Questioner:   Kieren
Category:  Advanced Math
Private:  No
 
Subject:  maths ratios
Question:  A High School had an enrolment of 1150 pupils. The ratio of boys to girls was 23:27.

Here is the basic ten principles for ratios:

A ratio is a fraction.
A ratio is a fraction.
A ratio is a fraction.
A ratio is a fraction.
A ratio is a fraction.
A ratio is a fraction.
A ratio is a fraction.
A ratio is a fraction.
A ratio is a fraction.
A ratio is a fraction.

>>So the ratio of boys to ALL was 23/(23+27) = 23/50, which means that 23/50 of the 1150 were boys, and 27/50 of 1150 were girls.

a. How many boys were enrolled.
b.How many girls were enrolled.
Could you please help me with the working out of this question.
Answer: a. 529 boys,
      b.  621 girls

..................................

Also
Population of a town has 38250 males and 30600 females.

a. what is the ratio of males to females

>> The ratio is  38250/30600, which you may want to reduce to lowest terms, which, as you noted below, is 5/4.



b.If 2000 males come to live in the town, how many extra females are needed to maintain the same ratio

So the same ratio applies to the new people:

boys      5
------ = ---
girls     4

2000      5
------ = ---
girls     4

girls = 4/5(2000) = 1600


Answer:a. 5:4
     b.1600 females

Thankyou for your help