Question

If the mean of the following frequency distribution is 28.5, find the value of p.
x 15 20 25 30 35 40
f 8 7 P 14 15 6​

Answer 1

Answer:

mean=120+140+25p+420+525+240/8+7+p+14+15+6

28.5=1445+25p/50+p

28.5×50+p=1445+25p

1425+28.5p=1445+25p

28.5p-25p=1445-1425

3.5p=20

p=20/3.5

p=20/35×10

p=5.7