A collection of 19 coins consisting of nickels and dimes is worth $1.35. How many dimes are there

There are 8 dimes there.

Step-by-step explanation:

This question is solved used a system of equations.

I am going to say that:

x is the number of nickels.

y is the number of dimes.

19 coins

This means that x + y = 19.

A nickel is worth $0.05. A dime is worth $0.1. The total of these coins is $1.35. So

0.05x + 0.1y = 1.35

How many dimes are there?

We have to find y.

From the first equation: x = 19 - y.

Replacing in the second:

0.05(19 - y) + 0.1y = 1.35

0.95 - 0.05y + 0.1y = 1.35

0.05y = 0.4

y = 0.4/0.05

y = 8

There are 8 dimes there.