Answer
The interval of increasing fat is\[\left( 25,65 \right)\] and that for decreasing fat is\[\left( 65,75 \right)\].
Work Step by Step
From the given graph it can be observed that:
At the age of 25, the percent body fat in men is 23.
Then the body fat percentage starts to increase until it reaches 26 at the age of 65.
Thus, in the graph, the interval in which the percent of body fat in men is increasing is $\left( 25,65 \right)$.
Then the body fat percentage starts to decrease until it reaches 25 at the age of 75.
Thus, in the graph, the percent body fat in men is decreasing on the interval $\left( 65,75 \right)$.
Therefore, the percent body fat in men increases in the interval $\left( 25,65 \right)$ and decreases in the interval $\left( 65,75 \right)$.
