Question 686291
Not sure your info is correct. "He has 3 times as many as nickles" ... 3 times as many as what to nickles? Three times the pennies? 

I will assume pennies is 3 times the number of nickles.
Let the number of pennies be P. Nickles be N. Dimes are D

Given that
You are told the sum of the money is 52 cents.
Thus 
{{{P + 5N + 10D = 52}}}
{{{P = 3N}}}
{{{N - 2 = D}}}
So plug all that in and solve for N
{{{3N + 5N + 10(N-2) = 52}}}
{{{8N + 10N - 20 = 52}}}
{{{18N - 20 = 52}}}
{{{18N = 72}}}
{{{N = 4}}}
So he has 4 nickles. Use that to solve for P and D
P = 12, D = 2
Check your answers. Do 2 dimes, 4 nickles and 12 pennies equal 52 cents?