Abowling ball traveling with constant speed hits the pins at the end of a bowling lane 16.5 m long. the bowler hears the sound of the ball hitting the pins 2.50 sec after the ball is released from his hands. what is the speed of the ball? the speed of sound is 340 m/s.

S = V(Tb) or V = S/Tb --- call this Equation 1
S = 340(Ts) --- call this Equation 2
where
S = length of the bowling alley
V = speed of the bowling ball
Tb = time for bowling ball to hit the pins after being thrown
Ts = time for sound to travel back to the bowler after pins are hit
Tb + Ts = 2.5
Ts = 2.5 - Tb and substituting this into Equation 2,
S = 340(2.5 - Tb) or solving for "Tb"
Tb = 2.5 - S/340 = 2.5 - 16.5/340
Tb = 2.45 sec.
Substitute this calculated value of "Tb" into Equation 1,
V = 16.5/2.45
V = 6.73 m/sec.
hope it helps