Let x be the number of friends.
He wants to give out 2x bars and have 10 left and he has 16 bars so the expression is:-
2x + 10 = 16
now he can solve for x to find the number of friends he can treat.
There are 1751 members under the age of 25.
Velocity with wind = 1,980 / 4.5 = 440 mph
Velocity against wind =1,980 / 5.5 = 360 mph
Plane in still air - wind speed = 360
Plane in still air + wind speed =440
Adding both equations:
2*Plane in still air = 800
Plane in still air = 400 mph
Plane in still air + wind speed =440
Therefore, wind speed = 40 mph
Consider the circle with center X, as shown in the figure.
Draw the diameter of the circle which is parallel to cherd AB, as shown in the figure.
Since the diameter and AB are parallel, then the line segment XC which bisects AB at C, will be perpendicular to AB.
SO triangle XCB is a right triangle. Thus the length of CX, by the Pythagorean theorem is

units.
Answer: 8 units