Mary mixes white paint and blue paint in the ratio 2: 3. she makes a total of 20 litres of paint. how much more blue paint does she need to add to the mixture so that the ratio of white paint to blue paint is 1: 7

8

step-by-step explanation:

this is a subtraction problem.

10 - 2 = 8

where is the image?

step-by-step explanation:

- "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."