Question

Parking lot has 121 spots. Ratio of senior to junior is 7 to 4. How many spots go to each grade level?

Answer 1

I am going to build a chart this is best when using ratios

seniors junior total
7 4
*? *? *?
Totals 121

The way we fill out this chart is that we add the rows and multiply the columns.

So we add 7 + 4 and fill it in our chart we get 11

seniors junior total
7 4 11
*? *? *?
Totals 121

now to find the *? need to divide 121/11 to get *?

121/11 = 11

so now our chart looks like this
seniors junior total
7 4 11
11 11 11
Totals 121

Now we multiply each column

so
7 * 11 = 77
4*11 = 44

now our chart look like this

seniors junior total
7 4 11
11 11 11
Totals 77 44 121

so seniors get 77 spaces
and juniors get 44 spaces.