Explanation

Co-prime numbers have no common factor except 1.

Their HCF (Highest Common Factor) is 1.

2, 4

• Factors of 2 = 1, 2
• Factors of 4 = 1, 2, 4
• Common factors = 1, 2
• HCF = 2  Not co-prime

3, 6

• Factors of 3 = 1, 3
• Factors of 6 = 1, 2, 3, 6
• Common factors = 1, 3
• HCF = 3  Not co-prime

4, 10

• Factors of 4 = 1, 2, 4
• Factors of 10 = 1, 2, 5, 10
• Common factors = 1, 2
• HCF = 2  Not co-prime

2, 9

• Factors of 2 = 1, 2
• Factors of 9 = 1, 3, 9
• Common factor = 1
• HCF = 1 Co-prime

Last updated 17 july 2026 by NA

Explanation

• The sum of the three interior angles of a triangle is 180°.
• This rule applies to all types of triangles.
• If two angles are known, the third angle = 180° − (sum of the other two angles).
• It is a basic rule of geometry.
• This property is known as the Angle Sum Property.

Last updated 17 july 2026 by NA

Explanation

Formula: nCr = n! / r!(n-r)!

Here n = 6 girls, r = 3 girls to select

6C3 = 6! / 3!(6-3)!  

= 6! / 3!3!  

= (6 x 5 x 4) / (3 x 2 x 1)  

= 120 / 6  

= 20

Last verified on 11-07-2026

Explanation

Any non-zero number raised to the power 0 is always 1.

So, (1/2)° = 1

Last verified on 10-07-2026

Explanation

• nPr represents the number of arrangements of r objects selected from n objects.
• In permutation, the order of objects matters.
• Different arrangements are counted as different results.
• It is used when the position or sequence is important.
• Formula: nPr = n! / (n − r)!

Last verified on 07-07-2026

Explanation

Use the formula: (n − 2) × 180°.

For a pentagon (n = 5): (5 − 2) × 180° = 540°.

Last verified on 06-07-2026

Explanation

Area of rectangle = length × width  

Length = 4, Width = 3  

Area = 4 × 3 = 12

Last verified on 25-06-2026

Explanation

Ladder + wall + ground make a right triangle.  

Angle = 45° at ground, distance from wall = 5m = adjacent side  

tan45° = opposite / adjacent = height / 5  

tan45° = 1, so height = 5 × 1 = 5m

Last verified on 24-06-2026

Explanation

Let width = w

Height = w + 6

Perimeter of rectangle = 2(length + width)

= 2(w + (w + 6))

= 2(2w + 6)

= 4w + 12

Last verified on 24-06-2026

Explanation

Let width = w cm  

Then length = w + 6 cm  

Perimeter of rectangle = 2(length + width)  

2(w + 6 + w) = 48  

2(2w + 6) = 48  

4w + 12 = 48  

4w = 36  

w = 9 cm  

So width = 9 cm, length = 9 + 6 = 15 cm.

Last verified on 23-06-2026