Mathematics for IGCSE & O level - Rates (Section 1 - No. 38)
A runner's average speed in an 80m race is 7 m/s. Find the time she takes for the race, to the nearest 0.1 second.
11.4 s
11.5 s
11.6 s
11.7 s
คำอธิบาย
Time = Distance / Speed = 80 m / 7 m/s ≈ 11.42 s, rounding to 11.4 s.