Answer:
The speed of the jet in still air is 260 miles per hour.
Explanation:
Given that a small jet can fly 858 miles in 3 hours with a tailwind but only 702 miles in 3 hours into a headwind, to find the speed of the jet in still air the following calculation must be performed:
858/3 = 286
702/3 = 234
(286 - 234) / 2 = X
52/2 = X
26 = X
286 - 26 = 234 + 26
260 = 260
Therefore, the speed of the jet in still air is 260 miles per hour.