Maths Common

Question 1

Congruent triangles Rules

Answer 1

SSS side, side, side
SAS side angle side
ASA angle side angle
RHS right angle, hypotonus, side

NO AAA angle angle angle

Question 2

Angles in a parallel line name

Answer 2

Corresponding angle angles are the same
Alternate angles angles are the same
Vertically opposite angles are the same

Question 3

Assumptions made when using a sampling

Answer 3

The sample is representative of the whole population
The sample was picked at random

Question 4

Types of Frequencys

Question 5

https://imgur.com/a/Dd05pyO

Answer 5

200<x≤300 not 250 you don’t need to half the class except when using it for a calculation

Question 6

https://imgur.com/a/GRE3yQl

Mean in frequency tables

Answer 6

We need fX (number of devices times number of house holds ) then add them up is the total amount of devices

For mean add all fX to get the total amount of devices and then divide by the total amount of household, if the amount of devices was a range e.g. 3<x≤9 you need to use the middle value of the range e.g. 6 and divide that by the total amount of devices

Question 7

https://imgur.com/a/urv2EHK

Median and range in frequency tables

Answer 7

For range look at the difference between the smallest value with a non zero frequency and the the largest value with a non zero frequency

For Median use (n+1)/2 to get the position of the median value (n being the total of the frequencies) ,then use the position of median value and count to get the shoe size e.g. if the median value is 7 and the first class has a frequency of 4 and the second class has a frequency of 5 the median value will be in the second class

Question 8

What do you do if it says prove that x is a value between these two numbers

Answer 8

Make the equation equal to zero substitute in one of the numbers and then the other number if there is a sign change e.g. -3 then 5 means the value of X is between those two numbers