Answer:
24 boys & 20 girls
Step-by-step explanation:
Last year:
Number of boys = x
Total number = 45
Number of girls = 45 - x
An increase of 20% is the same as multiplying by 1.2
A decrease of 10% is the same as multiplying by 0.8
This year:
New number of boys: 1.2x
New number of girls: 0.8(45 - x)
New total number = 45 - 1 = 44
1.2x + 0.8(45 - x) = 44
1.2x + 36 - 0.8x = 44
0.4x + 36 = 44
0.4x = 8
x = 20
Last year there were 20 boys and 25 girls.
This year there are 20 * 1.2 = 24 boys
and 44 - 24 = 20 girls
Answer: 24 boys & 20 girls
