The average life-span of a True Test auto battery is 42 months with a standard deviation of 4 months. Assume a normal distribution.
We can expect 95% of the batteries to last between Answer
and Answer
months.
We can expect % of the batteries to last less than 30 months.
We can expect % of the batteries to last longer than 42 months.
We can expect % of the batteries to last between 30 and 38 months.
We can expect
% of the batteries to last between 42 and 50 months