Answer:
The number of pennies,nickels and dimes are (p,n,d)=(3,4,6).
Further explanation:
Given:
A box holding pennies, nickels and dimes contains thirteen coins in a box.
Total value is 83 cents.
Calculation:
Consider p,n and d be the number of pennies, nickel and dimes.
Now, total is 13 coins so 
As we know that these following are US coin.
Penny=1 cent
Nickel=5 cents
Dime=10 cents
Step 1:
The value is already given as 83 cents that is 80+3 cents.
80 cents can be possible in many combinations as follows:
(N,D)=(0,8),(2,7),(4,6),(6,5),(8,4),(10,3),(12,2),(14,1),(16,0)
It is given that the total number of cents is 13 so we choose (4,6) as (n,d)
.
So the value of nickel n=4
Dimes d=6
Step 2:
The value of p is calculated as follows:
Substitute 4 for n, 6 for d in equation
as follows:


p=3
Thus, the number of pennies,nickels and dimes are (p,n,d)=(3,4,6).