Explanation

Mean = (6 + 8 + 10 + 12) ÷ 4

= 36 ÷ 4

= 9

Last verified on 15-05-2026

Explanation

Mean = (5 + 7 + 9) ÷ 3

= 21 ÷ 3

= 7

Last verified on 14-05-2026

Explanation

Find the mean of:

Numbers: 7, 6, 10, 8, 9

Frequencies: 2, 2, 5, 1, 2

Step 1: Multiply each number by frequency

7 × 2 = 14

6 × 2 = 12

10 × 5 = 50

8 × 1 = 8

9 × 2 = 18

Step 2: Sum of products

14 + 12 + 50 + 8 + 18 = 102

Step 3: Total frequency

2 + 2 + 5 + 1 + 2 = 12

Step 4: Mean

Mean = 102 ÷ 12 = 8.5

Last verified on 12-05-2026

Explanation

Average of 8 persons = 12.5

So total weight:

$$8 times 12.5 = 100$$

One person of 18 kg is replaced by 10 kg:

New total:

$$100-18+10=92$$

New average:

$$92÷8=11.5$$

$$Last\; updated\; question\; NS\; on\; 10\; MAY\; 2026$$

Explanation

Average of 3 numbers = 26

So total sum:

$$3\times 26=78$$

Given:

• First number = 16
• Second number = 31

Sum of first two:

$$16+31=47$$

Third number:

$$78 - 47 = 31$$

$$Last\; updated\; question\; NS\; on\; 10\; MAY\; 2026$$