Question

If each edge of a cube is decreased by 40%, find the percentage change in the surface area of the cube.

Answer 1

Answer:

         64% decrease

Step-by-step explanation:

Let s be original length of each edge.

Decreasing the edges by 40% results in a new length:

  t = s  -  40% of s

    = 60% of s

    = 0.6 × s

The original surface area is

    S = 6s²

The new surface area is

    T = 6t² = 6 × (0.6 × s)² = 0.36 × 6s²

⇒  T = 0.36 × S

⇒  T = 36% of S

⇒  T = S  -  64% of S

⇒  T = S decreased by 64%.

Answer 2

Step-by-step explanation:

दिस इज नॉट माय राइटिंग दिस इज गूगल राइटिंग l