Word Problems

Question 1

when you see “P is X percent of Q”, what do you write down?

Answer 1

P = X/100 *Q

Question 2

Distance =

Answer 2

D = rate * time

Question 3

Work

Answer 3

W = rate * time

Question 4

When dealing with rates, what would be a smart number?

Answer 4

a multiple of the two rates

Question 5

When two or more workers are working together, their rates can be what?

Answer 5

added together

Question 6

If one worker is undoing the work of another, their rates can be what?

Answer 6

subtracted

Question 7

Average or mean

Answer 7

sum/# of term

Question 8

A weighted average of only two values will do what?

Answer 8

fall closer to whichever value is weighted more heavily

Question 9

Median

Answer 9

Odd # of terms - unique middle value when terms are ordered in increasing order
Even # of terms - average of two middle values

Question 10

Small SD

Answer 10

List is clustered closely around the mean

Question 11

Large SD

Answer 11

List is spread out widely around the mean

Question 12

Variance equals what?

Answer 12

V = (standard deviation)^2

Question 13

Range of a list

Answer 13

Largest # - Smallest #

Question 14

Q1, Q2, Q3

Answer 14

Found by taking the mean of the largest number of quartile and the smallest number of the next quartile

Question 15

Q2 is the same as what?

Answer 15

the median

Question 16

Boundary for 1 SD away from the mean of a Normal Distribution

Answer 16

17% (left)

83% (right) (1/3 or 33% each way)

Question 17

Boundary for 2 SD away from the mean of a Normal Distribution

Answer 17

2% (left)

98% (right) (48% each way)

Question 18

% past 3 SD away from the mean of a Normal Distribution

Answer 18

.1% each way

Question 19

Fundamental Counting Principe

Answer 19

Multiply the number of individual decisions together

ex. 2 bun x 3 hot dogs

Question 20

1!`

Answer 20

1

Question 21

2!

Answer 21

2

Question 22

3!

Answer 22

6

Question 23

4!

Answer 23

24

Question 24

5!

Answer 24

120

Question 25

6!

Answer 25

720

Question 26

How to find the number of arrangements for an anagram

Answer 26

Take the factorial

Question 27

How do find the number of combinations when order does matter (ex 7C3)

Answer 27

7C3 = 7!/4! (number of options! / numbers of options - unwanted!)

Question 28

How do you find the number of combinations when order doesn’t matter (ex 7C3)

Answer 28

7C3 = 7!/(4!3!) (number of options! / number of wants! * number unwanted!)

Question 29

If there is a question with multiple sets of pools to choose from, what do you do?

Answer 29

Find each separately then multiply

Question 30

Probabilty

Answer 30

number of wanted outcomes/number of possibilities

Question 31

Way of finding probabilities (like coin flips)

Answer 31

counting tree

Question 32

How to determine if X AND Y will happen

Answer 32

Prob of X * Prob of Y

Question 33

How to determine if X OR Y will happen

Answer 33

Prob of X + Prob of Y

Question 34

How to find if X OR Y will happen when X and Y can happen at the same time

Answer 34

Prob of X + Prob of Y - Prob of (X AND Y)