Question

Debra saved only dimes and nickels in her bank. When she last counted the coins, she noticed there were twice as many dimes as nickels. She has $4.75 in her bank. how many dimes did she have in her bank?

A. 12
B. 24
C. 19
D. 38
please help me:)

Answer 1

Let n be the number of nickels and d be the number of dimes
Then
d=2n (given)
Therefore
d*(0.1)+n*(0.05)=4.75
Then
2n*(0.1)+n*(0.05)=4.75
Then
n*(0.2)+n*(0.05)=4.75
Then
n*(0.2+0.05)=4.75
Then
n*0.25=4.75
Then
n = 4.75÷0.25 = 19
Then
d =2n = 38