Answer:
1/4 or 0.25
Step-by-step explanation:
*I'm assuming you're asking about the probability of this happening...
There are 4 different results you can get when flipping a coin twice...
First Flip: heads
Second Flip: tails
First Flip: heads
Second Flip: heads
First Flip: tails
Second Flip: heads
First Flip: tails
Second Flip: tails
only one of these is heads, then tails, so our probability is
1/4, or 0.25