How do you write 1/3 as a decimal?

2 Answers
Nov 8, 2016

0.3

Explanation:

I ideally believe in significant figures, so I would rather write it down as 0.3.

Most people will write it down as 0.33, 0.333, 0.3333, etc.

Since it is just a constant run on of 3's, there is no rounding up, so best bet, and safest would be 0.3

If it were 2/3, then the best would be to write it down as 0.67, since you want to clarify that you rounded up the 0.666

Nov 8, 2016

1/3 = 0.3333333..... = 0.bar3
In practice use 1/3 as 0.333 or 0.33 , depending on the level of accuracy required.
1/3 is exact and therefore accurate.

Explanation:

The fraction 1/3 is awkward to write as a decimal because it recurs.

1/3 = 0.3333333..... = 0.bar3

The amount of rounding wil depend on the level of accuracy required in a particular situation.

Normally 3 significant figures might be expected. 1/3 = 0.333

If only 1 decimal place is given, it can be seen as 0.3 = 3/10 whch is not the same as 1/3 = 3/9

I would suggest that either 0.33 or 0.333 be used, or just the fraction 1/3 which is exact and therefore accurate.