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4 years ago

Joanna has a total of 7 rolls of coins worth $23. She has rolls of dimes worth $5 each, and

Mathematics

1 answer:

yawa3891 [41]4 years ago

6 0

Answer:

3 rolls of dimes and 4 rolls of nickels

Step-by-step explanation:

Number of rolls of dimes = x

Number of rolls of nickels = y

Total number of rolls = 7

x + y = 7 -------------------(i)

Total amount = $ 23

5x + 2y = 23 ----------------(ii)

Multiply equation (i) by -2. So when we are adding, y will be eliminated and you will get the number of rolls of dimes.

(i)*(-2) -2x - 2y = -14

(ii) <u>5x + 2y = 23</u> {Now add}

3x = 9

x = 9/3

x = 3

Plug in the value of x in equation (i)

3 +y = 7

y = 7- 3

y = 4

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