Answer:
105
Step-by-step explanation:
It is easy to calculate: add up all the numbers, then divide by how many numbers there are. In other words it is the sum divided by the count.
(91+89+X)/3 =95
91+89+X =95*3
180+X =285
X =285 - 180
=105
42.194988
There are 42.194988 km in 1 marathon
