Question

1) Hypermetropia can be corrected by?
a) Convex lens b) Bifocal glass
c) Concave lens
d) Convex mirror​

Answer 1

Question :-

3 equal cubes each side 7 cm are joined end to end .find the surface area of resulting cuboid.

Answer :-

Surface Area of cuboid = 686 cm².

Given :-

Side = 7 cm { 3 cubes }

Have to Find :-

What is the Surface Area of Resulting Cuboid .

Calculations :-

We know that ,

Surface area of the cuboid = = 2(lb + bh + hl).

Now ,

Substituting the values in the above formula :-

↬ 2(21 × 7 + 7 × 7 + 7 × 21).

↬ 2(147 + 49 + 147).

↬ 2(343).

↬ 686 cm²

Hence ,

The required answer is = $686 {cm}^{2}$

Additional Information :-

Perimeter of Rectangle = 2( L + B )

Perimeter of square = 4 × Side

Perimeter of triangle = AB + BC + CA

Area of Rectangle = L × B

Area of Square = ( side ) ²

Area of Rhombus = Product of Diagonal/2.

Area of Parallelogram = Base × Height.

Area of triangle = ½ × base × height .