5 cylinders are built successively , the first is 4 meters tall and the following cylinders are each 4 meters taller than the previous . if the perimeter is 10 pi m , what is the total surface area of the 5 cylinders , excluding the bases of each cylinder ?
s . a . = h x p + 2 x a we need to excude the bottom area , so the formula becomes : s . a . = h x p + a p = 2 pi x r , so 10 pi = 2 pi x r r = 5 since we have 5 cylinders with different heights the equation becomes s . a . = ( 4 + 8 + 12 + 16 + 20 ) x 10 pi + 5 x pi x r ^ 2 60 x 10 pi + 5 pi x 5 ^ 2 600 pi + 125 pi = 725 pi sq . m . answer is a
surface_cylinder(divide(10, const_2), add(add(multiply(4, const_4), add(multiply(4, const_3), add(4, multiply(4, const_2)))), add(multiply(4, const_3), add(4, multiply(4, const_2)))))