Upload
others
View
3
Download
0
Embed Size (px)
Citation preview
S2 (2.4) L2 Fractions & Percentages.notebook December 02, 2014
Daily Practice 30.9.2014
Q1. 67.5 x 50
Q2. Round 67.22 to the nearest unit
Q3. Work out the surface area of this cube
Q4. Work out the volume of this cuboid
Q5. £60 - £45.04
4cm
60cm30cm
20cm
Today we will be learning how to find a
fraction of an amount.
To find a fraction of an amount simply means to divide the amount
by whatever the denominator of the fraction is.
Examples:
1. Find of 365 2. Find 1/8 of 220 3. Find 1/9 of 2790 1/5
Finding Fractions of Quantities 30.9.2014
Draw the following cross word box into your jotter, using the
squares in your jotter as a guide and then complete it.
Daily Practice 2.10.2014
The top of a fraction is called the numerator.The bottom of a fraction is called the denominator.
To find a fraction of an amount where the top of the fraction > 1*Divide by the bottom, multiply your answer by the top of the fraction*
Examples:
(i) Find 2/3 of 33 (ii) Find 4/7 of 2849 (iii) Find 3/8 of 1604
Finding Fractions of Quantities 2.10.2014
S2 (2.4) L2 Fractions & Percentages.notebook December 02, 2014
1 2/3 of 15 2 3/4 of 16 3 3/7 of 14 4 3/5 of 35
5 4/9 of 27 6 3/4 of 28 7 6/7 of 49 8 2/5 of 15
9 6/7 of 56 10 3/5 of 10 11 8/9 of 18 12 3/4 of 20
13 2/7 of 28 14 3/8 of 24 15 5/6 of 18 16 7/9 of 36
Finding Fractions of Quantities 2.10.2014 Finding Fractions of Quantities 2.10.2014
Simplifying Fractions
Simplifying Fractions
To simplify a fraction, just divide top and bottom by a common factor.
To fully simplify it, divide by the HCF.
Examples: Simplify the following fractions
(a) (b) (c) (d)
Q1. Calculate the volume of a cube with sides of length 7cm
Q2. 3277 + 1459
Q3. Solve 7g + 2 = 16
Q4. State the value of 3g2 when g = 4
Q5. Write out the 5 times table up to 5 x 12
Daily Practice 6.10.2014
S2 (2.4) L2 Fractions & Percentages.notebook December 02, 2014
Questions: Simplify the following
(a) (d) (g)
(b) (e) (h)
(c) (f) (i)
Simplifying Fractions
Equivalent Fractions
An equivalent fraction is just another way of writing a fraction.
For example
If you multiply top and bottom by the same number (it can be any number), you will get an equivalent fraction.
Examples: Write two equivalent fractions for the following
Questions: Write equivalent fractions for the following
(a) (d) (g)
(b) (e) (h)
(c) (f) (i)
Equivalent FractionsDaily Practice 7.10.2014
Q1. 78.22 + 38.313
Q2. Calculate the volume of this cuboid
Q3. Simplify the fraction
Q4. 320 ÷ 50
Q5. Simplify 3m + 2m - 1m + 10m
10cm4cm
5cm
Today we will be learning how to compare fractions.
Homework Due Friday
S2 (2.4) L2 Fractions & Percentages.notebook December 02, 2014
Comparing Fractions Comparing Fractions
Comparing Fractions Daily Practice 9.10.2014
Q1. Round 87.226 to 2 decimal places
Q2. Calculate the volume of a cuboid with length 6cm, breadth 7cm and height 5cm
Q3. Solve 5x - 1 = 19
Q4. Find the value of 4d2 - 2 when d = 3
Q5. Simplify the fraction
Today we will be converting fractions so that we can compare
them numerically.
Homework Due tomorrow!
Comparing Fractions
To compare two fractions in terms of size, they need to have the same denominator.
We can find the common denominator by finding the LCM of both the denominators.
Examples:
1. 2.
and and
S2 (2.4) L2 Fractions & Percentages.notebook December 02, 2014
Comparing Fractions
For the following fractions:
1. Convert your fractions so that they have a common denominator.
2. Write down a <, >, or = sign between these fractions to show which is bigger or if they are equal.
(a) (b) (c) (d)
Adding & Subtracting Fractions Adding & Subtracting Fractions
Fractions can only be added/subtracted if they have the same denominator.
Ensure that you use the LCM to make the denominators the same.
Examples:
1. 2. 3.
Daily Practice 4.11.2014
Q1. Round 89.225 to the nearest unit
Q2. Calculate the volume of a cuboid with length 5cm, breadth 4cm and height 10cm
Q3. What is the lowest common multiple of 3 and 5?
Q4. Simplify the fraction
Q5. What is the area of this triangle?
5cm
6cm
Today we are going to learn how to find a
percentage of an amount.
S2 (2.4) L2 Fractions & Percentages.notebook December 02, 2014
Percentages 4.11.14
A percentage is a fraction whose denominator is 100.
1% = 8% = 20% =
13% = 50% = 98% =
Percentages 4.11.14
To find a percentage of an amount - Think about the percentage as a fraction, then it is the same as finding a fraction of an amount.
Examples: Work out the following
a) 1% of 700 b) 16% of 800 c) 28% of 2000
Percentages 4.11.14
Questions:
a) 1% of 1000 b) 4% of 300 c) 2% of 800 d) 9% of 100
e) 3% of 800 f) 19% of 500 g) 28% of 700 h) 34% of 300
i) 7% of 3000 j) 43% of 900 k) 40% of 7000 l) 38% of 1000
m) 14% of 4000 n) 30% of 10000 o) 8% of 120 p) 10% of 23
q) 2% of 34 r) 7% of 2.5 s) 5% of 78 t) 16% of 90000
Daily Practice 6.11.2014
Q1. Find 3/5 of 630
Q2. Round 145.223 to 1 decimal place
Q3. Write 6 hours and 45 minutes in decimal form
Q4.How many sides does a heptagon have?
Q5. Calculate the surface area of a cube with sides of length 8cm
Today we will be learning to simplify percentages
Percentages 6.11.14
What happens when...
*Simplify the fraction so the denominator is an easy number to divide with.
Examples:
a) Find 20% of 62 b) Find 25% of 72 c) Find 75% of 328
Find 40% of 87
S2 (2.4) L2 Fractions & Percentages.notebook December 02, 2014
Q1. 25% of 800 Q9. 50% of 321
Q2. 40% of 720 Q10. 20% of 600
Q3. 20% of 900 Q11. 80% of 740
Q4. 10% of 72 Q12. 70% of 900
Q5. 80% of 35 Q13. 30% of 80
Q6. 90% of 90 Q14. 10% of 43
Q7. 60% of 40 Q15. 20% of 65
Q8. 70% of 50 Q16. 60% of 320
Percentages 6.11.14Percentages 6.11.14
Rather than simplify each time, try to remember a few of the key ones:
10%
20%, 30% etc.
25%
50%
75%
331/3%
662/3%
Finding percentages of amounts
Questions:
(a) Find 25% of 80 (b) Find 2% of 400 (c) Find 80% of 700
(d) Find 7% of 200 (e) Find 331/3% of 360 (f) Find 90% of 90
(g) Find 10% of 340 (h) Find 50% of 350 (i) Find 75% of 840
(j) Find 662/3% of 18 (k) Find 30% of 70 (l) Find 5% of 600
Daily Practice 7.11.2014
20 Questions Mental Maths
Today we will be learning to do percentages
questions in context.
Percentages of amounts
Examples:
1. 40% of entrants to a course are male. If there are 270 people on the
course, (i) how many are male?
(ii) How many are female?
2. A TV costs £750, in the sale it is marked 25% off. How much does it
cost in the sale?
S2 (2.4) L2 Fractions & Percentages.notebook December 02, 2014
Percentages of amounts
Make up a question in context on percentages.
You must be able to work out the question without the use of a
calculator.
Daily Practice 10.11.2014
Q1. Round 78.8 to the nearest unit
Q2. Find 80% of 36
Q3. Solve 4x - 5 = 27
Q4. Write 4.25 hours in hours and minutes
Q5. Calculate the distance Derek travels if he drives at a speed
of 55mph for 3hours
Today we will be learning how to write fractions as
percentages.
Homework Online due Friday 14.11.14
Writing Fractions as percentages
Fractions as percentages without using a calculator:
Turn the fraction into an equivalent fraction over 100. (This can only work if the denominator is a factor of 100)
What are the factors of 100??
S2 (2.4) L2 Fractions & Percentages.notebook December 02, 2014
Writing Fractions as percentagesExamples: Write the following fractions as percentages
1. 2.
3. 4.
Questions: Turn these into percentages