math 2

Question 1

Primary Data

Answer 1

Primary Data is data I collected myself

Question 2

Secondary Data

Answer 2

secondary data is collected by someone else.

Question 3

How do you take primary data

Answer 3

Different ways of collecting primary data include questionairres, surveys and data logging

Question 4

What is population

Answer 4

The total number of items your suevey relates to is called the population

Question 5

What is a sample

Answer 5

The group of items you test is called a sample

Question 6

For a sample to be reliable and unbiased, it should

Answer 6

be at least 10% of the population and represent the population

Question 7

the more larger the sample

Answer 7

the more reliable it is

Question 8

what is a random sample

Answer 8

A random sample, the whole population has an equal chance of being chosen, so it reduces the chances of being biased

Question 9

A good question should not be

Answer 9

unclear
leading
restrictive

Question 10

Leading question meaning

Answer 10

A leading question encourages people to give a particular answer

Question 11

a grouped frequency table has how many classes?

Answer 11

4 or 5 equal width classes

Question 12

When y and x are in direct proportion, what is constant?

Answer 12

y / x is constant

Question 13

What is the symbol for proportion?

Answer 13

∝

Question 14

if y and x are in proportion, what does the k mean in y=kx

Answer 14

when y ∝ x,then y =kx, the k is the constant of proportionality

Question 15

percentage change formula

Answer 15

percentage change = actual change / original amount * 100

Question 16

how do you say if something is inversely proportional?

Answer 16

y ∝ 1/x, y = k/x, applies the same for the opposite values (e.g x = …)

Question 17

what do you do if a number is to the power of a fraction

Answer 17

a^(m/n)

(n squareroot(a))^m

Question 18

What is a right prism

Answer 18

is a prism where the cross-section is at right angles to the length of the solid

Question 19

what is perfect square

Answer 19

x^2 + 2ax + a^2

Question 20

What is translation notation

Answer 20

(4 3) the top value is left or right and bottom is up or down (left is negative, bottom is negative)

Question 21

how do u find the true value of something

Answer 21

Lets say something was decreased by 25%
u find the other part of it 75%
then u add it to the equation that x * 0.75 = whatever value and u divide it from there
lets say something was increased by 25%
u say x * 1.25 = whatever value and u divide it from there

Question 22

What is a bearing

Answer 22

Is an angle in degrees, measured clockwise from North. A bearing is always written using three digits, like 025

Question 23

What is the scale on a map

Answer 23

The scale on a map is given as a ratio 1:2. For example, 1:25000 means that 1cm on the map represents 25000cm in real life.

Question 24

Give the the 5 reasons to prove if a triangle is congruent

Answer 24

SSS (Side, side side)
SAS (Side, angle side)
ASA (Angle side angle)
AAS (Angle angle side)
RHS (Right Angle Hypotenuse Side)

Question 25

Give the reason to prove why a triangle is similar

Answer 25

AAA (Angle Angle Angle)

Question 26

What is congruent

Answer 26

Where all angles, number of sides and side lengths is the same.

Question 27

What is similar

Answer 27

Where all the angles and number of sides is the same but the side lengths can change.

Question 28

how do u convert between compound measures like km/hr to m/s

Answer 28

first lets say 500km/hr u change that to 500000m/hr then its 500000/3600s

Question 29

What is density, how do u measure it, what letter represents it

Answer 29

ρ symbolizes density, denisty measures the mass per unit volume, g/cm3 or kg/m3

Question 30

Density formula driangle

Answer 30

M DV

Question 31

Pressure formula driangle

Answer 31

F PA

Question 32

What is the units for pressure

Answer 32

Pascals, N/cm2 or N/m2

Question 33

What is an upper bound and lower bounds

Answer 33

The biggest possible actual value is called the upper bound/ The smallest possible actual value is called the lower bound.

Question 34

What is the absolute error

Answer 34

The absolute error is the maxiumum difference between the measured value and the actual value, u can do this by finding the first upper bound then dividing it by how many objects

Question 35

How do u find the equation of a line between 2 points like A (4, 2) B (9, 17)

Answer 35

y = mx + c solve it usuing simultaneos equations A: x = 4, y = 2 2 = 4m + c B: x = 9, y = 17 17 = 9m + c 17 = 9m + c 2 = 4m + c 15 = 5m m = 3 2 = 12 + c c = -10 y = 3x - 10

Question 36

How to mix two densities in a ratio

Answer 36

u multiply the ratio values with the density and and do the same for the other one and add them together. Then divide it by the sum of the ratio.

Question 37

How to find the perpendicular line of a line in a chart

Answer 37

So You take the gradient of the line you are creating a bisector for and put it as a denominator and make it negative so like 4 is the gradient so the perpendicular would be -1/4

Question 38

what is qualatiitve data

Answer 38

Data that isnt numeric

Question 39

What is cumulative frequency

Answer 39

The frequency that is like added up as you go on through the table