Question

38 is replaced by 18 in a data of 10 numbers. How is the mean affected ?​

Answer 1

Answer:

Step-by-step explanation:sum of 3 numbers=29*3=87

sum of 2 numbers=38*2=76

3rd number=87-76=11

Answer 2

Let initial mean = x1+x2+x3+38...+x10 ----- 1

                                            10

new mean = x1+x2+x3+18...+x10 ------2

                                  10

now 1-2 gives us:

--->initial mean-new mean= 20/10

---->initial mean - new mean= 2

----->so new mean = initial mean-2

Hence the new mean has decreased by 2.