Explanation

Given:

Increment in number = 20% of the number

Decrement in number = 20% of the new number

Concept used:

Net increase or decrease percent = {(Original number or Final number) - (Final number or original number) ÷ Original number} × 100

Calculation:

Let the original number be 100

When the number is increased by 20%

New Number = 100 + 20% of 100

⇒ 100 + 20

⇒ 120

Now, the number is decreased by 20%

Final number = New number – 20% of new number

⇒ 120 – 20% of 120

⇒ 120 – 24

⇒ 96

∴ Net Decrease in percentage = { (100 – 96) / 100} × 100

⇒ {4/100} × 100

⇒ 4%

∴ The net decrease percentage is 4%.

Last verified on 11-07-2026

Explanation

Given:

Side of square = 2.5 cm

Formula:

Perimeter=4×Side

Calculation:

=4×2.5

=10 cm

Explanation

2 + 3 = 5

5 + 7 = 12

12 + 11 = 23

23 + 15 = 38

38 + 19 = 57

57 + 23 = 80

Last verified on 31-03-2026

Explanation

Series: 13, 32, 24, 43, 35, ?, 46, 65, 57, 76

Notice the pattern alternates:

+19, −8, +19, −8, +19, −8, +19, −8, +19

So:

35 + 19 = 54

Then 54 − 8 = 46, which matches.

Explanation

The sum of the interior angles of a polygon can be calculated using the formula:

(n-2) × 180°, where n is the number of sides.

For a hexagon, n = 6.

Sum of interior angles = (6-2) × 180°

= 4 × 180°

= 720°

Last verified on 07-10-2026