Kobe went to local bank to get $20 in quarters, dimes and nickels for his restaurant. He got twice as many quarters as dimes. Also, he got 10 more nickels than

Question

Kobe went to local bank to get $20 in quarters, dimes and nickels for his restaurant. He got twice as many quarters as dimes. Also, he got 10 more nickels than dimes. How many of each type of coin did he get?

Answer 1

Hi Aryiss;

 

q= number quarters

d = number dimes

n =number nickels

 

Each quarter is $0.25, dimes are $0.10, nickels are $0.05:

0.25q + 0.1d + 0.05n = 20   {equation 1}

 

q = 2d

n = d + 10

 

Using substitution we can easily solve for d, number of dimes:

 

0.25(2d) + 0.1d + 0.05(d+10) = 20

 

Multiply through by 100 to clear the decimals and make it easier:

 

25(2d) + 10d + 5(d+10) = 2000

50d + 10d+5d + 50 = 2000

65d + 50 = 2000

65d = 1950

d = 1950/65

d = 30 dimes

 

Can you use the original information to find

the number of quarters and nickels?