Assume the tuner does not overshoot the target. Assume the beat frequency decreases monotonically from the initial to final values.

! Required information A piano tuner sounds two strings simultaneously. One has been previously tuned to vibrate at 252.0 Hz. The tuner hears 7.00 beats per second. The tuner increases the tension on the as-yet untuned string, and now when they are played together the beat frequency is 1.00 s-1. By what percentage did the tuner increase the tension on that string? %