Explanation

Area of circle = πr²  

Circumference = 2πr

Given: Area = 275 m²

1. Find radius r:

πr² = 275

r² = 275 / π = 275 / 3.1416 ≈ 87.54

r = √87.54 ≈ 9.356 m

2. Find circumference:

C = 2πr = 2 × 3.1416 × 9.356 ≈ 58.78 m

Last verified on 05-08-2026

Explanation

We can use tan to find the height.

Given:

Person's height = 1.6 m 

Distance from tower = 20 m

Angle of elevation = 45°

Let h = height of tower above the person's eye level.

In the right triangle:

tan(45°) = opposite / adjacent = h / 20

We know tan(45°) = 1

So: 

1 = h / 20

h = 20 m

This is the height from eye level to top of tower.

Total height of tower = h + person's height

= 20 m + 1.6 m 

= 21.6 m

Last verified on 05-08-2026

Explanation

Perimeter of rectangle = 2 × (Length + Width)

Given: 

Length = 58.7 

Width = 23.2

Perimeter = 2 × (58.7 + 23.2)

= 2 × 81.9

= 163.8

Last verified on 05-08-2026

Explanation

LCM of 5, 7, 10, 12 = 420 seconds

1 hour = 3600 seconds

Number of complete intervals:
3600 ÷ 420 = 8.57

Since the first strike is excluded, the number of complete strikes is 8.

Explanation

Formula: Area = r × s

Semi-perimeter: s = Perimeter ÷ 2 = 8 ÷ 2 = 4 cm

Therefore: r = Area ÷ s = 72 ÷ 4

= 18 cm

Explanation

15 cm, 20 cm, 25 cm  

15^2 + 20^2 = 225 + 400 = 625  

25^2 = 625  

625 = 625 

Last verified on 28-07-2026

Explanation

The wall = 4 m high  

Distance from wall = 3 m  

Ladder = hypotenuse

Use Pythagoras theorem:  

c² = a² + b²  

c² = 3² + 4²  

c² = 9 + 16  

c² = 25  

c = √25 = 5

Last verified on 28-07-2026

Explanation

The volume of the cubic room is 2744 m³. To find the length, we need to find the cube root of 2744.

Cube root of 2744 = 14

So, the length of the room is 14 m.

Last verified on 26-07-2026

Explanation

• R = abc / 4Δ is the formula for the Circumradius of a triangle.
• R = Circumradius
• a, b, c = Lengths of the three sides
• Δ = Area of the triangle

Last updated 24-07-2026 by NA

Explanation

The decimal number is 11.

Binary uses only 0 and 1.

11 = 8 + 2 + 1.

Binary place values: 8, 4, 2, 1.

Therefore, 11₁₀ = 1011₂.

Last update 0n 21-07-2026 by NA