Emma correctly answered 21 of 25 questions. what percent of the question did Emma answer correctly?
A.21%
B.84%
C.16%
D.96%
E. None correct

Work Shown:

21/25 = 84/100 after multiplying top and bottom by 4

Since 84/100 = 84%, this means 21/25 = 84% as well

Alternatively, you can use a calculator or long division to find that 21/25 = 0.84 = 84%

- "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."