Question

In a school gym, the ratio of the number of boys to girls was 4:3. After 160 boys left the gym, the ratio become 4:5. How many girls were there in the gym

Answer 1

Girls never change number

make same
4:3 times 5 is 20:15
4:5 times 3=12:15


boys:girls
from 20:15 to 12:15
boys dropped 160

20-12=8
160=8 units
divide both sides by 8
20=1unit

girls=15 units
20*15=300

300 girls