Question

Two identical spinners each have five equal sectors that are numbered 1 to 5. What is the probability of a total of 7 when you spin both spinners?

Answer 1

`"Prob"("sum"=7)=4/25=16%`

Explanation:

`{: ("sum = 7?",,"|","spinner A",,,,,), (,,"|",,1,2,3,4,5), ("-------------","---",,"--------","----","----","----","----","----"), ("spinner B",,"|",,,,,,), (,1,"|",,N,N,N,N,N), (,2,"|",,N,N,N,N,color(red)(Y)), (,3,"|",,N,N,N,color(red)(Y),N), (,4,"|",,N,N,color(red)(Y),N,N), (,5,"|",,N,color(red)(Y),N,N,N) :}`

As we can see from the above table `4` out of a possible `25` combinations give a total of `7`

So the probability is `4/25`