- A school has 617 students. Each class has between 28 and 32 students.
Which is the best estimate of the
number of classes in the school?
A
14 classes
B)
20 classes
30 classes
D
60 classes

B) 20 classes

Step-by-step explanation:

4a. is 3 miles every hour

4b. is 1/3 of an hour per mile

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."