Decimals are used in situations where money is used. Coins are fractions of a dollar and are expressed as decimal values. Pennies are $0.01, nickels are $0.05, dimes are $0.10, and quarters are $0.25. Different amounts of these coins can give us any fraction of a dollar, from $0.01 to $0.99.

Just line up the decimal points, and (if necessary) add zeros to the end of one number, so they have the same number of decimal places. Then add (or subtract) as you usually would. In your answer, the decimal point should go exactly below where it is in the numbers being added (or subtracted).

You should become efficient in using the four basic operations involving decimals—addition, subtraction, multiplication, and division.

We use decimals every day while dealing with money, weight, length etc. Decimal numbers are used in situations where more precision is required than the whole numbers can provide. For example, when we calculate our weight on the weighing machine, we do not always find the weight equal to a whole number on the scale.

Answer: 0.05 as a fraction is written as 1/20.

Examples of percentages used in the real world

1. One of the most common ways that fractions are used is money. A quarter is 1/4 of a dollar, a dime is 1/10 of a dollar, a nickel 1/20 and a penny 1/100.
2. Another way we use fractions is when we cook, when we want ingredients we measure them with fractions e.g. 1/4 flour.

The third significant figure of a number is the digit after the second significant figure. We round a number to three significant figures in the same way that we would round to three decimal places. We count from the first non-zero digit for three digits. We then round the last digit.

significant figures
By KATIE ROSS. In the GCSE exams for any of the sciences you could be asked to write an answer to a certain number of decimal places (d.p.) or significant figures (s.f.).