Maths help please!

[MagisCapulus]

Please can anyone with the attached?.

Distance is speed x time. Where the speed is increasing, or decreasing, it is doing so at a constant rate, so you can take an average over the period.

Robin goes from 0 to 5 m/s (ie average speed 2.5 m/s) over 20 seconds, which is 50m. Then 50 seconds at 5 m/s, which is 250m. In the last 40 seconds his average is 2.5 m/s again, so 50m. In total, he has travelled 400 metres in 110 seconds.

Sanjay accelerates from 0 to 6 m/s over 60 seconds, so an average of 3m/s covering 180m. He is then traveling at 6 m/s and needs to cover a further 220m. Dividing 220 by his speed of 6, it will take him 36.7 seconds. In total, he took 96.7 seconds to cover 400 metres.

Hope this helps.

Brilliant thank you!