Suppose we flip four coins simultaneously: a penny, a nickel, a dime, and a quarter. What is the probability that the penny and dime both come up the same?
so we have 16 orders and there are 2 orders that make the penny and dime both come up the same so the probability is 1/8
edited:reson oops I solved the wrong problem
I'm not sure if you were right or wrong...
The question has some ambiguity so It's best to leave both answers.
Does your question mean ONLY them come up the same or at LEAST?
SO.
I'll go with least.
There is a 1/2 chance dime gets same as penny.
If penny is heads, 1/2 dime head, etc.
If it's ONLY...
1/2 chance, and 1/2*1/2 chance that the other ones are NOT the same, so 1/8 of getting the same, if ONLY the penny and dime are the same.