Math Et Cetera

Question 1

Probability

Answer 1

Think of probability in terms of fractions. Probability = number of possible outcomes that satisfy the condition / number of total possible outcomes If it is impossible for something to happen then the numerator is 0 and probability is equal to 0 if something is certain to happen then the numerator and denominator are equal and probability is equal to 1

Question 2

Two Laws of Probability Probability of A and B Probability of A or B

Answer 2

Probability of A and B = probability of A x probability of B Probability of A or B = probability of A + probability of B

Question 3

Factorials

Answer 3

The factorial of a number is equal to that number times every positive whole number smaller than that number. Break it out, cancel out shared parts.

Question 4

Permutations and Combinations

Answer 4

Permutation is an arrangement of things in a particular order. To solve a permutation - Figure out how many slots you have - Write down the number of options for each slot - Multiply them Combination is just a group and the order of elements in the group doesn’t matter. To solve a combination - Figure out how many slots you have - Fill in the slots as you would with a permutation - Divide by the factorial of the number of slots the denominator of the fraction will always cancel out completely, so you can cancel first before you multiply

Question 5

Functions and Funny-Looking Symbols

Answer 5

Don’t let it throw you, just follow the instructions.

Question 6

Groups

Answer 6

Use the group equation when confronted by a group problem. T = G₁ + G₂ - B + N

T represents the Total, G₁ is one group, G₂ is the second group, B is for the members in both groups, and N is for the members in neither group.