Question

the mean of 20 nos is 18 . if 3 is added to each of first 10 nos. . find the mean of new set kf 20 numbers.​

Answer 1

Answer:

19.5

Step-by-step explanation:

Sum of 20 nos = 20 * 18 =360

Now 3 added to 10 nos so sum will increase by 30 .

So new sum = 360 + 30 = 390

So new average

$\frac{390}{20} = 19.5$