Answer:
about 0.196
Step-by-step explanation:
4 + 18 + 10 + 8 = 40, this means that the piggy bank has 40 coins in total. Probability of the FIRST coin being a dime is 18/40 and the probability of the SECOND coin being a dime too is 17/39. To find the answer you would multiply 18/40 x 17/39.
18/40 x 17/39 = 306/1560 = about 0.196
Hope this helps :D