Let the sides of the base are 5k, 12k and 13k, respectively.
Given, perimeter of base = 60 cm
⇒ 5k + 12k + 13k = 60

Correct Option: A

Let the sides of the base are 5k, 12k and 13k, respectively.
Given, perimeter of base = 60 cm
⇒ 5k + 12k + 13k = 60
∴ k = 60/30 = 2
The sides of base are 10 cm, 24 cm 26 cm.
∴ Volume of prism = (1/2) x 10 x 24 x 50 = 6000 cm³

Volume of prism = Area of base x Height
Weight of prism = volume x density

Correct Option: D

Volume of prism = Area of base x Height
= (1/2) x 10 x 12 x 20
= 1200 cm²

∴ Weight of prism = 1200 x 6
= 7200 g
= 7.2 kg

According to the formula,
Percentage decrease in surface area = [2 x (-24) + (-24) x (-24)/100]%

Correct Option: C

According to the formula,
Percentage decrease in surface area = [2 x (-24) + (-24) x (-24)/100]%
= [-48 + 5.76]% = - 42.24%

According to the formula
Percentage increase in surface area = [ 2x + x²/100]%

Correct Option: A

According to the formula
Percentage increase in surface area = [ 2x + x²/100]%
= [2 x 3 + (3)²/100]%
= [6 + 0.09]%
= 6.09%

Let length, breadth and height be 4k, 3k and 2k, respectively.
Whole surface area = 2(lb + bh + lh)
⇒ (lb + bh + lh) = 8788/2 = 4394
⇒ (4 x 3 + 3 x 2 + 2 x 4 ) k² = 4394

Correct Option: B

Let length, breadth and height be 4k, 3k and 2k, respectively.
Whole surface area = 2(lb + bh + lh)
⇒ (lb + bh + lh) = 8788/2 = 4394
⇒ (4 x 3 + 3 x 2 + 2 x 4 ) k² = 4394
⇒ 26k² = 4394
⇒ k² = 169
⇒ k = 13
∴ Length = 4k = 4 x 13 = 52 cm