Question

A collection of dimes and nickels has a total value of two dollars and contains 28 coins. How many dimes are there in the collection?

A.)14 dimes

B.)8

C.)12

D.)10

Answer 1

You were supposed to make a system of equations and solve it by elimination. the answer is C and here’s how i solved it. I hope this helps you out and helps you understand this topic a bit more :)

Answer 2

12 dimes

Explanation:

Let :

Dime = x

Nickel = y

Dime is worth 10 cent = $0.1

Nickel is worth 5 cent = $0.05

x + y = 28 - - - (1)

0.1x + 0.05y = 2 - - - (2)

From (1)

x = 28 - y

0.1(28 - y) + 0.05y = 2

2.8 - 0.1y + 0.05y = 2

2.8 - 0.05y = 2

2.8 - 2 = 0.05y

0.8 = 0.05y

y = 0.8 / 0.05

y = 16

x = 28 - 16

x = 12