Algrebra Question! Please help fast!! word problem!!

Question

Kendra has $5.25 in dimes and nickels. If she has 3 times as many dimes as nickels, how many of each coin does she have?

Answer 1

Let d be the number of dimes n number of nickels. Then 10d+5n=525 cents ($5.25) and d=3n. So

10(3n)+5n=525

35n=525

n= 15

d=3n=45

Check: 45*10+15*5=450+75 =525 cents=$5.25