Spring 9

Question 1

Here is a vector:
(x)
(y)
What does x and y represent?

Answer 1

x = right
y = up

Question 2

Here is a vector:
(-a)
(-b)
What does a and b represent?

Answer 2

a = left
b = down

Question 3

Here is a vector:
(f)
(-g)
What does f and g represent?

Answer 3

f = right
g = down

Question 4

Define congruent

Answer 4

Shape: Same size and shape
Angles: Same measure (degrees)
Sides: Same length

Question 5

Define similar

Answer 5

Two figures that have the same shape. Ratios of lengths or angles are equal (e.g. enlargement).

Question 6

What are the three important things to remember about bearings?

Answer 6

1) Measured from north.
2) In a clockwise direction.
3) Written as three figures.

Question 7

Complete the sentence:

The mean is always…

Answer 7

…between the lowest and highest numbers.

Question 8

What does Σ mean?

Answer 8

Sigma, meaning “sum of”.

Question 9

What does ∅ mean?

Answer 9

“Empty set”

Question 10

What does A ∩ B mean?

Answer 10

A intersect B (both A and B)

Question 11

What does A ∪ B mean?

Answer 11

A union B (A, B or both)

Question 12

What does A’ mean?

Answer 12

Not A

Question 13

What does A ∪ B ∩(A ∩ B)’ mean?

Answer 13

A union B but not A intersect B

Question 14

What does ∩ mean?

Answer 14

But/And

Question 15

Define positive correlation

Answer 15

As one quantity increases so does the other.

Question 16

Define negative correlation.

Answer 16

As one quantity increases, the other decreases.

Question 17

Define no correlation.

Answer 17

Both quantities vary with no clear relationship.

Question 18

What should you do when asked to estimate values of one variable in comparison to the other on a graph?

Answer 18

Draw the line of best fit.

Question 19

On scatter graphs, how can we describe the relationship between the data?

Answer 19

We can describe the relationship as:
A positive correlation
A negative correlation
No correlation

Question 20

The line of best fit…

Answer 20

Shows the general trend of two points.
Must be straight
Does not have to go through the origin or any of the points

Question 21

Frequency polygons are…

Answer 21

Plotted at the midpoint

Drawn with straight lines

Question 22

What do you need to help you find out the average in a set of grouped data?

Answer 22

Data
Frequency (f) and total
Midpoint (mp)
Midpoint * Frequency (mp*f) and total

Question 23

How do you find the maximum range with a set of grouped data?

Answer 23

Highest Nº in data - Lowest Nº in data = range

Data table

Question 24

How do you find the modal group with grouped data?

Answer 24

Look at which group has the highest frequency (frequency table).

Question 25

How do you find the mean estimate in a set of grouped data?

Answer 25

mp*f total / f total = mean estimate | mp*f table, frequency table

Question 26

How do you find the median in a set of grouped data?

Answer 26

f total / 2 = x Add frequencies up until you reach x (frequency table)

Question 27

On a map with a scale of 1:3,000,000 the distance between Edinburgh and London is 18cm. What is the actual distance, in kilometres, between these cities?

Answer 27

``` 18cm*3,000,000cm = 54,000,000cm 100cm = 1m 54,000,000/100 = 540,000m 1000m = 1km 540,000/1000 = 540km ```

Question 28

The actual distance between two places in 2.4km. If a map has a scale of 1:40,000 what distance on the map is used to represent it?

Answer 28

2.4km = 2400m 2400m = 240,000cm 240,000/40,000 = 6cm

Question 29

Point B is 100m away from point A. The map uses a scale of 1:1000. What distance is shown on the map to represent this?

Answer 29

100cm = 1m 100cm*100 = 10,000cm 10,000cm/1000 = 10cm

Question 30

Rewrite the interval 11-20 using inequalities.

Answer 30

10.5 < x ≤ 20.5

Question 31

Rewrite the interval 31-40 using inequalities.

Answer 31

30.5 < x ≤ 40.5