Please help! I am really confused on how to show my work. Someone please guide me through how I solve this and I MIGHT mark you as brainliest answer! ;) ;>

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

Mr. and mrs. wallace have decided to buy a car for $21,600. they finance $15,000 of it with a 5-year auto loan at 2.9% arp. what will be their monthly payment be? a. $268.20 b. $268.86 c. $269.54 d. $387.16 i need !

[10 points, algebra 2-simplifying complex fractions]according to my answer key the restrictions are -1 and 4. but why not positive 1?