Explanation

First 4 even numbers: 2, 4, 6, 8

Sum = 2 + 4 + 6 + 8 = 20

Average = 20/4 = 5

Last verified on 15-02-2026

Explanation

Mean =  numbers of multiples/ sum of multiples of first five of 3

The average of the first five multiples of 3

= 3 + 6 +9 + 12 + 15 / 5

= 45/ 5

= 9

Last verified on 15-02-2026

Explanation

The sum of the first 10 natural numbers is:

1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10 = 55

Average = 55/10 = 5.5

OR

Formula for natural number= n(n+1)/2

n=10

Now

10(10+1)/2

10(11)/2

5(11)

55

Last verified on 15-02-2026

Explanation

Total marks = 87 + 85 + 92 + 78 + 68 = 410

Number of subjects = 5

Average = 410/5 = 82

Last verified on 07-02-2026

Explanation

Calculate Initial Age: The boy is 3 years old, and his sister is 3 times older.

This means she is  3 x 3 =9years old.

Find the Age Difference:

The constant age difference between them is 9-3 = 6 years.

Calculate Future Age: When the boy reaches 11 years old, the sister will still be 6 years older than him.

Final Result:  11 + 6 = 17