Number
What are the first 4 multiples of 8?
8, 16, 24, 32
Is the following event certain, likely, unlikely or impossible?
In a bag of 5 red, 5 blue and 5 green counters, I take a yellow counter out at random.
Impossible - there are no yellow counters!
What is the range of this list of numbers:
8, 2, 2, 3, 6, 4, 8, 5
Range = Biggest - Smallest
= 8 - 2
= 6
Solve x + 15 = 26
x = 26 - 15 = 11
How many degrees are there in a right angle?
90o
What are the factors of 15?
Factors are the numbers you can divide by.
1, 3, 5, 15
Is the following event certain, likely, unlikely or impossible?
In a classroom 20 students, 13 of which are boys, I pick a girl at random.
20 - 13 = 7
So there are 13 boys and 7 girls.
It is unlikely that a girl will be picked.
What is the mode from the following list of numbers:
5, 2, 5, 6, 7, 2, 3, 2, 1
Mode = most common number
= 2
Solve 7x = 56
x = 56 ÷ 7 = 8
What do the 3 angles inside a triangle add up to?
180o
What are the prime numbers between 20 and 30?
Prime numbers are numbers that only have 2 factors.
23 and 29
What is the probability as a fraction that when I roll a fair 6-sided dice that I get a 5?
There are 6 numbers on a 6-sided dice (1,2,3,4,5,6), only one of which is a 5.
So the probability you roll a 5 is
1/6
Work out the mean of the following numbers:
10, 6, 17, 14, 3
Mean = Total of the numbers ÷ How many there are
Total of the numbers = 50
50 ÷ 5 = 10
22 - 7 = 15
15 ÷ 3 = 5
x = 5
What is the area of a rectangle with a base of 9cm and a height of 7cm?
Area = Base x Height
= 9 x 7 = 63cm2
Work out the following: 18 + 45 ÷ 32
Use BIDMAS!
32 = 9
45 ÷ 9 = 5
18 + 5 = 23
What is the probability as a fraction that when I roll a fair 6-sided dice that I get a factor of 6?
The factors of 6 on the dice are 1, 2, 3 and 6.
So there are 4 numbers that are a factor out of a total of 6 numbers.
So the probability you roll a factor of 6 is
4/6
What is the median of the following list of numbers:
5 10 8 11 9 4
Median = middle of the ordered data
Ordered Data = 4 5 8 9 10 11
Middle values = 8 and 9 so median = 8.5
Simplify 9a -2b -4a + 8b
9a - 4a = 5a
-2b + 8b = 6b
Answer: 5a + 6b
What is the name of a regular 7-sided shape?
Heptagon / Septagon
Work out 54 x 73
7 3
x 5 4
2 19 2
31 6 5 0
1 9 4 2
= 1942
A bag contains 20 marbles that are red, blue, yellow or green.
There are 3 yellow marbles and 9 red marbles.
The probability I pick a blue marble is the same as a green marble.
What is the probability I pick a green marble as a fraction?
3 + 9 = 12
20 - 12 = 8 marbles left (blue or green)
Probability of blue and green is the same so 8 ÷ 2 = 4 marbles each
So the probability I pick a green marble is
4/20
I'm thinking of 3 numbers.
They have a range of 2.
They have a mean of 6.
There is no mode.
What are they?
5, 6, 7
7 - 5 = 2
5 + 6 + 7 = 18 18 ÷ 3 = 6
No mode
Substitute x = 3 into 5x2 - 7x
x2 = 9
5 x 9 = 45
7 x 3 = 21
45 - 21 = 24
How many mm in 5.2m?
1m = 100cm
So 5m = 500cm and 5.2m = 520cm
1cm = 10mm
So 500cm = 5000m and 520cm = 5200mm