Answer:
There are 16 nickels and 10 dimes in the jar.
Explanation:
Given:
A jar contains n nickels and d dimes.
There are 26 coins in the jar.
The total value of the coins is $1.80.
Now, to find the number of nickels and dimes in the jar.
As given nickels =

And dimes =

So, the total number of coins:

........(1)
The value of a nickel = $0.05.
And the value of a dime = $0.10.
Now, the total value of the coins:

Putting the value of
from equation (1) we get:
⇒

⇒

⇒

Subtracting both sides by 2.6 we get:
⇒

Dividing both sides by -0.05 we get:
⇒

So, the number of nickels = 16.
Now, to get the number of dimes we put the value of
in equation (1):

⇒

⇒

Thus, the number of dimes = 10.
Therefore, there are 16 nickels and 10 dimes in the jar.