Question

A number, n, rounded to the nearest 10 is 640.

Another number,p, rounded to the nearest 10 is 430.
What are the lower nd upper bounds of n+p

Answer 1

1080

Explanation:

Answer 2

The lowest each number could be before being rounded would be 635 and 425 since if it’s five or over you round up; the highest each could be is 644 and 434 since if it’s four or under you round down.

635+425= 1060 (lower bound)
644+434=1078 (upper bound)