The probability of a bolt being faulty is 0.3. Find the probability that in a random sample of 20 bolts there are
a) exactly 2 faulty bolts
Under 2nd VARS on a TI-84,
binompdf(20,0.3,2)
0.0278458725
b) more than 3 faulty bolts
1 - P(less that or equal 3)
Under 2nd VARS on a TI-84,
1 - binomcdf(20,0.3,3)
1 - 0.1070868045
0.8929131955
these bolts are sold in bags of 20, Sam buys 10 bags
c) find the probability that exactly 6 of these bags contain more than 3
faulty bolts.
The probability that 1 bag has more than 3 faulty bolts is 0.8929131955.
binompdf(10,0.8929131955,6)
0.0139964719
Edwin
