Mr. smith is appointed as the principal of a school. in order to keep the building safe, he appoints 2 hall monitors for every hallway, and 4 supervisors for every 20 hall monitors. mr. smith’s school has 30 hallways. how many supervisors does mr. smith need to appoint?

2 monitors for each hallway, 30 hallways, this means there are 60 total monitors. There are 3 sets of 20 monitors, and 4 for each set, which means that there are 12 supervisors needed to be appointed.

step-by-step explanation:

we are given

since, we have to isolate x on anyone side

so, we can move all x terms on one side

subtract both sides by 2x

add both sides by 9

divide both sides by 4

we get

if you are saying purchasing 3 social media ads and one newspaper ad counts as one purchase then there are:

6 purchases

if you are asking how many of each then:

18 social media ads

6 newspaper ads