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.