SOLUTION: In a school, 45% the students are boys and the rest are girls.If girls number is 77,what is the strength of the school ?

Algebra ->  Percentage-and-ratio-word-problems -> SOLUTION: In a school, 45% the students are boys and the rest are girls.If girls number is 77,what is the strength of the school ?      Log On


   

Question 1108447: In a school, 45% the students are boys and the rest are girls.If girls number is 77,what is the strength of the school ?
Answer by greenestamps(13203) About Me  (Show Source):
You can put this solution on YOUR website!


You can solve this using a proportion.

The boys are 45%, so the girls are 55%. Since the number of girls is 77, if x is the number of boys then
45%3A55+=+x%3A77
9%3A11+=+x%3A77
x+=+63

So there are 63 boys; then the total number of students is 77+63 = 140.

Alternatively, you could just say since 55% of the total number of students (the girls) is 77, if x is the total number of students then
0.55x+=+77
x+=+77%2F0.55+=+140