Answer:
The coins of each type are, 17 nickel coins and the 5 quarter coins.
Step-by-step explanation:
Given:
Liliana has $2.10 in nickels and quarters in her purse.
She has 12 more nickels than quarters.
Now, to find the coins of each type she have.
Let the number of nickels be

Let the number of quarters be

The total worth of coins = $2.10.
The value of a quarter is $0.25 and the value of a nickel is $0.05.
According to question:

⇒

⇒

Adding both sides by 3 we get:
⇒

Dividing both sides by 0.30 we get:
⇒

The number of nickels = 17.
Now, to get the number of quarters we put value of
:


The number of quarters = 5.
Therefore, the coins of each type are, 17 nickel coins and the 5 quarter coins.