the answer is 5.4
Explanation:
3 is 3/4 of 4. this means the figure on top is 3/4 the size of the figure on the bottom. so x = 3/4(7.2)
3/4 is equal to .75, so if you multiply 7.2 by .75 (multiplying it by 3/4), you get the measure of x. in this case, x = 5.4
i hope this helps you in the future! :)