The average daily sales of 500 branch offices was Rs. 150 thousand and the standard deviation was Rs.15 thousand. Assuming the distribution is normal, find how many branches have sales between (i) Rs. 1,20,000 and Rs.1,45,000 (ii)Below 140,000 and (iii) More than 1,65,000 Solution u=150,000 s=15,000 i) x1=120000 z1=(x1-u)/s = -2 x2=145000 z2=(x2-u)/s = -0.33 P(120000.

1. The average daily sales of 500 branch offices was Rs. 150 thousand and the standard deviation
was Rs.15 thousand. Assuming the distribution is normal, find
how many branches have sales between
(i) Rs. 1,20,000 and Rs.1,45,000
(ii)Below 140,000 and
(iii) More than 1,65,000
Solution
u=150,000 s=15,000
i)
x1=120000 z1=(x1-u)/s = -2
x2=145000 z2=(x2-u)/s = -0.33
P(120000