By failing to prepare, you are preparing to fail.
Home/Standard/Data & Statistics/Normal Distribution/Reply To: Normal Distribution

Maths Made Easy Forums Standard Data & Statistics Normal Distribution Reply To: Normal Distribution

Keymaster
Post count: 659

A wood saw cuts timber to an average length of 1200mm, with a standard deviation of 6mm. What are the limits of timber that would “very probably” lie between?

“very probably” means within 2 standard deviations

find the lower limit which means set 2 standard deviations below the mean

1200 – 2 × 6 = 1188

ind the upper limit which means set 2 standard deviations above the mean

1200 + 2 × 6 = 1212

∴ 1188mm – 1212mm