At a certain bookstore, you get a $5 coupon for every 4 books you buy. What is the least number of books you could buy to get $15 in coupons? Show your work.

12books

Step-by-step explanation:

4 books → 1 $5 coupon

$15 coupon = $15 / $5 = 3times of $5 coupons

3 $5 coupons → 4 x 3 = 12 books

this is a topic on forming and solving equations. If you wish to explore more into this topic you can give me a follow on Instagram (learntionary) I'll be posting notes for many topics and will also be posting some tips :)

- "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."