Bill is a builder. On Monday he made mortar mix.
He used 24kg of sand and 5 kg of cement.
On Tuesday Bill will make the same type of mortar mix.
He will use 36 kg of sand.
How much cement does he need to make the same type of mortar mix?

7.5 kg

Step-by-step explanation:

24 : 5

36 : x

x = 5 × 36 / 24

= 7.5 kg

- "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."