Question

What will be the total painted surface area of the block?

440 cm2

380 cm2

324 cm2

404 cm2

Answer 1

the cross section is a trapezium

total area = 2*area trapezia + area of the 4 rectangles

do you know how to get area of a rectangle?

Answer 2

like the base of this block?

Answer 3

area of a rectangle is = A = L*W

Answer 4

yes so area base = 10*12 = 120 cm2 right ?

Answer 5

yepp

Answer 6

ok so you can now find area of the back, top and slanting faces of the block given the supplied width and lengths.

area of each trapezium is 1/2 (7 + 10) / 4
7 and 10 are the 2 parallel sides and 4 is the height

Answer 7

so do you want to figure the area out?

Answer 8

yes

Answer 9

great

Answer 10

you have to calculate area of 4 rectangles and 2 trapezia (same area)
and add them up