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
Does your question mean ONLY them come up the same or at LEAST?
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.