Posted by margret on .
A collection of dimes is arranged in a triangular array with 14 coins in the base row, 13 in the next, 12 in the next, and so forth. Find the value of the collection.

math 
Reiny,
number of dimes
= 1+2+3+...+13+14
= 7(1+14) = 105
value = 105(.10) = $10.50