Question

What is the circumference of a circle if the diameter is 1.6?

Answer 1

Circumference `= 5.0`

Explanation:

Formula for circumference of circle is `pid`
`color(white)("XXXX")`where `d` is the diameter, and
`color(white)("XXXX")pi` (approximately `3.14159`) is a standard constant.

With a diameter of `1.6`
`color(white)("XXXX")`circumference `= pi*1.6`

`color(white)("XXXXXXXXXXXX")~~3.14159*1.6`

`color(white)("XXXXXXXXXXXX")~~ 5.02654`

Since the diameter is only given to 2 places of accuracy, the computed average should be rounded to 2 places as well:
`color(white)("XXXX")`circumference `= 5.0`