Rounding

Question 1

Rounding Rule if the last digit is 4 or less?

Answer 1

Leave the number the same

Question 2

Rounding rule if the last number is 5 or more

Answer 2

Round up

Question 3

Round 4.75

Answer 3

4.8

Question 4

Round 0.00356

Answer 4

0.0036
* Round the last digit and leave the zeros even if they are not s.f IN THIS CASE

Question 5

Round 2454. 96 to 2 s.f

Answer 5

2500
* it is 2 s.f because the 00 are not s.f because there is no decimal

Another way to solve is to put it in scientific notation:

2.45496x10^3 -> Then round to 2 s.f -> 2.5x10^3 -> Input that into calculator -> answer (2500)

Question 6

Round 10,776.522 to 3 s.f

Answer 6

10,800

• It has 3 s.f because the 0 sandwiched is s.f but the ones in the end are not becaus they don’t have a decimal before them

*Because it is asking for 3 s.f you can get rid of the .522 because if you left it than it would be more than 3 s.f

Question 7

Round 4.999902 x 10^6 to 3 s.f

Answer 7

5.00 x 10^6

• Because you are rounding to 3 s.f you see if the 4th digit is higher than 4 which it is so you round up and the rounding up carries over since it rounds up to 10.
  *cut the rest off because it is asking for 3 s.f