Solve the Problem $\$ 4.45$ If the Number of Dimes Were Doubled and the Dimes

Multiple Choice

Solve the problem.
-Joe has a collection of nickels and dimes that is worth $\$ 4.45$ . If the number of dimes were doubled and the number of nickels were increased by 15 , the value of the coins would be $\$ 7.30$ . How many dimes does he have?

A) 15 dimes
B) 21 dimes
C) 10 dimes
D) 47 dimes