Question

How do you round 315.757 to the nearest hundredth?

Answer 1

`315.76`

Explanation:

The cut of place for `1/100ths` is the second decimal place.
So the numbers we are interested in are the red ones below.

`color(red)(315.75)7`

But the 7 after the 5 is such that `7>=5` so we round up giving

`315.76`
'~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Another example

Suppose we had:
`color(red)(23.58)3`

The 3 is such that `3<5` so we round down (do not change anything giving 23.58
'................................................................
Suppose we had:
`color(red)(23.58)6`

`6>=5` so we round up giving 23.59