Question

A man has two more nickels than dimes. He has $1.15 in all. How many coins of each kind does he have?

Which equation can be used to solve the problem?

5x + 10(x + 2) = 115
5(x + 2) + 10x = 115
x + x + 2 = 115

Answer 1

5(x+2) + 10x = $1.15

7 dimes and 9 nickels

70 (7x10) cents and 45 (9x5) cents = 1.15

Answer 2

5(x +2) + 10x = 115

Number of nickels = 9 and dimes = 7

Explanation:

Let the number of nickels a man has = y

and dimes = x

Then by the statement of the question we can form the equation as

y = x + 2------(1)

(.05)y + (.10)x = 1.15------(2)

By multiplying equation 2 by 100

5y + 10x = 115-----(3)

Now we put the value of y from equation 1 in the equation 3

5(x + 2) + 10x = 115

5x + 10 + 10x = 115

15x + 10 = 115

15x = 105

x = 7

y = 7 + 2 = 9

Number of nickels = 9 and dimes = 7