In a particular manufacturing process, bricks are produced in batches of 10,000. Because of random variations in the manufacturing process, random errors occur in the target length of the bricks...

In a particular manufacturing process, bricks are produced in batches of 10,000.

Because of random variations in the manufacturing process, random errors occur in

the target length of the bricks produced. If the bricks have a mean length of 200 mm

with a standard deviation of 20 mm, show how the error function tables supplied can

be used to calculate the following:

(a) the number of bricks with a length between 198 and 202 mm.

(b) the number of bricks with a length greater than 170 mm.