1. A bank has determined that the monthly balances

Question

1.      A bank has determined that the monthly balances of customers' savings accounts are normally distributed with an average of $1,350 and a standard deviation of $250. What percentage of customers has a monthly balance over $1,150?

( )
a.
21.19%
( )
b.
28.81%
( )
c.
71.19%
( )
d.
78.81%
 
 

Answer 1

either c) or d) as over half will have a balance over $1,150. half are over $1,350

78.114% is most accurate. d) is closer than x)

z= 1350-1150)/250 = 200/250= 8/10 = .8 sds use z tables or a statistics calculator