Question

If the mean of following frequency distribution is 7.2 find the value of k

X 4 8 12 16 20 29

F 8 14 10 32 K 6

Answer 1

Answer:

mean= 32+112+120+512+20k+174/8+14+10+32+k+6

mean=950+20k/70+k

7.2×70+k=950+20k

504+7.2k=950+20k

504-950=20k-7.2k

446=12.8k

446/12.8=k

34.8=k