# MATHS FACTS YOU NEED TO KNOW

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MATHS FACTS YOU NEED TO KNOW
It will really help you improve your Maths if you learn all these facts! Have a go and then try to test yourself!!

Fractions, Decimals, Percentages
1/10 0.1 10% 2/10 0.2 20% 3/10 0.3 30% 4/10 0.4 40% 5/10 0.5 50% 6/10 0.6 60% 7/10 0.7 70% 8/10 0.8 80% 9/10 0.9 90% 10/10 1 100%

Fractions, Decimals and Percentages
1/4 0.25 25% 1/2 0.5 50% 3/4 0.75 75% 1/5 0.2 20% 2/5 0.4 40% 3/5 0.6 60% 4/5 0.8 80%

Test Yourself Write 4/10 as a decimal. What is 3/5 as a decimal?
Write 0.53 as a percentage. What is 75% as a fraction? Write ¼ as a percentage. What is ½ as a decimal? What is ½ as a percentage? Write ¾ as a decimal.

Answers Write 4/10 as a decimal What is 3/5 as a decimal? Write 0.53 as a percentage % What is 75% as a fraction? /4 Write ¼ as a percentage. 25% What is ½ as a decimal? What is ½ as a percentage? % Write ¾ as a decimal

Ordering Decimals To order a set of decimals, write them out directly underneath each other. Add place holders so each number has the same amount of digits Starting with the biggest number, look at each column in turn to work out the order

Test yourself! Order these sets of numbers, smallest first:
2.75, 27.5, , 11.1, 11.11, , , 11.01 217.71, , , , 271 0.28, 0.288, 0.208, 2.8, 2.801

Answers Order these sets of numbers, smallest first:
2.75, 27.5, , 2.277, 2.72, 2.75, , 27.5 11.1, 11.11, , , 11.01 11.01, , 11.1, , 11.11 217.71, , , , 271 217.17, , 271, , 0.28, 0.288, 0.208, 2.8, 2.801 0.208, 0.28, 0.288, 2.8, 2.801

Ordering mixed fractions, decimals and percentages
Always convert everything to either all fractions, all decimals or all percentages. 5/10, 48%, 0.45, 3/5, 35% Convert them all to a percentage 50%, 48%, 45%, 60%, 35% Then it is easy to order them!

Test yourself! Put these in order, starting with the smallest: 2/5, 43%, 0.25, 2/10, 20% ¼, 3/10, 2/5, 50%, 0.3 33%, 8/10, 2/5, ¾, 0.85

Test yourself! Put these in order, starting with the smallest: 2/5, 43%, 0.25, 2/10, 20% ¼, 3/10, 2/5, 50%, 0.3 33%, 8/10, 2/5, ¾, 0.85

Answers Put these in order, starting with the smallest:
2/5, 43%, 0.25, 2/10, 26% 2/10, 0.25, 26%, 2/5, 43% ¼, 3/10, 2/5, 50%, 0.32 ¼, 3/10, 0.32, 2/5, 50% 33%, 8/10, 2/5, ¾, 0.85 33%, 2/5, ¾, 8/10, 0.85

Equivalent fractions If a fraction is equivalent to ½, the top number will always be half the bottom number. 3/6, 7/14, 10/20, 40/80, 5/10 all all equivalent fractions

Equivalent fractions To find an equivalent fraction you need to multiply or divide the top and bottom by the same number. E.g. To find equivalent fractions for 4/6: multiply the top and bottom by 5 = 20/30, multiply the top and bottom by 3 = 12/18

Simplifying fractions
To simplify a fraction you need to find the biggest number you can equally divide the top and bottom by. E.g. To simplify 5/15, divide the top and bottom by 5 = 1/3 To simplify 40/90, divide the top and bottom by 10 = 4/9

Test yourself! Simplify these fractions: - 4/6 - 20/50 - 18/27 True or false? 15/40 is equivalent to ½. Explain your answer. True or false? 30/90 is equivalent to 1/3. Explain your answer.

- 4/ /3 (divide top and bottom by 2) - 20/50 2/5 (divide top and bottom by 10) - 18/27 2/3 (divide top and bottom by 9) True or false? 15/40 is equivalent to ½. Explain your answer. False, 15 is not half of 40 and if you simplify 15/40, it is 3/8. True or false? 30/90 is equivalent to 1/3. Explain your answer. True, if you divide 30 and 90 by 30 it is 1/3

The bigger the negative number, the colder it is The smaller the negative number, the warmer it is

Negative Numbers Always, always use a number line to add or subtract negative numbers = = 7 0 – 2 = – 10 = -3

Test yourself! What is 7 less than 3? What is -5 + 10?
The temperature on Monday was -2. On Tuesday the temperature rose by 8 degrees. What was the temperature on Tuesday? The temperature on Monday was 1 degree. It fell by 2 degrees each day. What was the temperature on Friday?

Answers What is 7 less than 3? -4 What is -5 + 10? 5
The temperature on Monday was -2. On Tuesday the temperature rose by 8 degrees. What was the temperature on Tuesday? 6 degrees The temperature on Monday was 1 degree. It fell by 2 degrees each day. What was the temperature on Friday? -7 degrees