Carlos biked 139 over 8 miles on Saturday and 135 over 7 miles on Sunday. On which day did he ride further and by how much? Carlos rode further on Saturday by 1 and 51 over 56 miles.
Carlos rode further on Saturday by 3 and 5 over 56 miles.
Carlos rode further on Sunday by 3 and 51 over 56 miles.
Carlos rode further on Sunday by 1 and 51 over 56 miles.

go on the tube you might find some information there

- "runner b is moving at a slower rate."

- "the graphs shown are graphs of distance(km) against time(min).

the slopes of this graphs are are given by:

slope = (change in y)/(change in x)

= (change in distance)/(change in time)

this is the formula for finding the speed. so, the slope of these graphs represent the speed of the runner.

taking each division in the graph to represent 1 on both axis:

runner a ⇒ speed = (2-0)/(1-0)

= 2/1

= 2 km/min

runner b ⇒ speed = (3-0)/(3-0)

= 3/3

= 1 km/min

this shows that   runner b is moving at a slower rate."