1.42 because you subtract 10 from the price
The line, shadow and the height form a right angled triangle so we can apply the Pythagoras theorem here:-
11^2 = h^2 + 8^2 where h = height of the kite
h^2 = 11^2 - 8^2
h^2 = 57
h = 7.55 ft to the nearest foot Answer
20 / 28 = 0,7
0,7 * 60 = 42
Dave should catch the bus at 6:48 PM.