Question

87 to the nearest 10

Answer 1

90 is the nearest 10.  You round up at 5 and above, you round down from 1 to 4.

Answer 2

Simple...

you have 87

if you look at the number in the tens place (8) and if you see the number behind it, in the ones place (7) is bigger than 5 round up.

90

Thus, your answer.