SOMEONE PLS HELP ME PLS

Determine the number of girls in a math class with 87 boys if there are 25 girls for every 75 boys

To decrease an amount by 16% what single multiplier would you use

Taber invested money in an account where interest is compounded every year. he made no withdrawals or deposits. the function a(t)=525(1+0.05)^t represent the amount of money in the account after t years. how much money did taber origanally invested?