Alright so what you are doing is getting the area of the whole triangle, and that formula is what you do so bxh is 5x12 and 5x12=60 then you need to divide 60 by 2 which is 30 so your answer will be
B 30m^2
Divide 2.48 by 10 to find the price of 1 slice. = 0.248
Do the same with the other price.
3.18 / 12 = 0.265
The best one to get would be the 10 cheese slices because a single slice is cheaper than the single slices for the 12 slices.
hope this helped! (:
The reciprocal of 10 2/3 is 3/32
Formula C= 2 pi r. Or C= pi d
3.14 times 25 = 78.5 in