Transcript MATHS FACTS YOU NEED TO KNOW

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
FRACTION
DECIMAL
PERCENTAGE
1/10
2/10
3/10
4/10
5/10
6/10
7/10
8/10
9/10
10/10
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Fractions, Decimals and Percentages
FRACTION
1/4
1/2
3/4
1/5
2/5
3/5
4/5
DECIMAL
0.25
0.5
0.75
0.2
0.4
0.6
0.8
PERCENTAGE
25%
50%
75%
20%
40%
60%
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. 0.4
• What is 3/5 as a decimal? 0.6
• Write 0.53 as a percentage. 53%
• What is 75% as a fraction?
3/4
• Write ¼ as a percentage.
25%
• What is ½ as a decimal?
0.5
• What is ½ as a percentage? 50%
• Write ¾ as a decimal.
0.75
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, 2.72. 2.277, 22.727
• 11.1, 11.11, 11.011, 11.101, 11.01
• 217.71, 217.17, 271.071, 271.017, 271
• 0.28, 0.288, 0.208, 2.8, 2.801
Answers
Order these sets of numbers, smallest first:
• 2.75, 27.5, 2.72. 2.277, 22.727
2.277, 2.72, 2.75, 22.727, 27.5
• 11.1, 11.11, 11.011, 11.101, 11.01
11.01, 11.011, 11.1, 11.101, 11.11
• 217.71, 217.17, 271.071, 271.017, 271
217.17, 217.71, 271, 271.017, 271.071
• 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.
Answers
• Simplify these fractions:
- 4/6 2/3 (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
Negative Numbers
• Always think of negative numbers as
temperature to help you
• 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
-3 + 6 = 3
0 – 2 = -2
-2 + 9 = 7
7 – 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