Practicing Success

Target Exam

CUET

Subject

General Test

Chapter

Quantitative Reasoning

Topic

Mensuration: 2D

Question:

A 9 cm solid metallic cube and a solid metallic cuboid having dimensions 5 cm, 13 cm, 31 cm are melted and recast into a single cube. What is the total surface area (in cm2)of the new cube?

Options:

865

1176

1362

2744

Correct Answer:

1176

Explanation:

We know that,

Side of cube = 9 cm

We have,

Length = 5 cm

breadth = 13 cm

height = 31 cm

Volume of Solid metallic cube = 93 = 729 cm3

Volume of Solid metallic cuboid = 5 × 13 × 31 = 2015 cm3

Volume cube = Volume of Solid metallic cube + Volume of Solid metallic cuboid= 729 + 2015 = 2744 cm3

Side of cube = (a)3 = 2744

a = 14 cm

Total surface area of cube = 6 × 14 × 14 = 1176 cm2