https://www.ocr.org.uk/blog/a-level-mathematics-how-accurate-is-a-mathematical-answer/
What does DP mean in rounding?
of decimal places
Rounding means reducing the number of decimal places (d.p.) a number has but keeping its value close to what it was. The purpose is to make the number simpler. Suppose we want to round a number to 2 decimal places (or 2 d.p.). To do this, we look only at the next digit to the right (the third decimal digit)
What is SF in rounding?
The method of rounding to a significant figure is often used as it can be applied to any kind of number, regardless of how big or small it is. When a newspaper reports a lottery winner has won £3 million, this has been rounded to one significant figure. It rounds to the most important figure in the number.
https://www.bbc.co.uk/bitesize/guides/zscq6yc/revision/3
https://www.physicsclassroom.com/
ukhomeschool 