You take the amount paid and divide it by the amount of cheese. So 10.50 divided by 2.5 equals 4.2 and 12.60 divided by 3 equals 4.2 meaning that one pound of cheese costs $4.20
I think it’s 6. There are 4 squares and 4 triangles. 2 triangles put together turn into a square, so that would make 2 extra squares. 4+2=6.

notice, that, pure juice is 100% juice, dohhh, thus 100/100 = 1.00
50% is 50/100 or 0.50 in decimal format
so..... whatever those two quantities amount to, that is, the 50% and pure juice, or (4)(0.50) + (x)(1.00)
they will equal the mixture desired 60% juice, or 0.60, namely (4+x)(0.60)
thus (4)(0.50) + (x)(1.00) = (4+x)(0.60)
solve for "x"
The shirts were sold at $15 each.