Arithmetic

Question 1

Irrational numbers

Answer 1

Square root of any number that is not a perfect square

Pic is irrational, decimals go forever and constantly changing

Question 2

Rational number

Answer 2

A number that can be represented by the quotient of two integers

Examples

5 = 5/1
.325 = 325/1000
1/3

Question 3

An even plus and even equals an

Answer 3

Even

Question 4

An odd plus an odd equals an

Answer 4

Even

Question 5

An odd plus an even equals an

Answer 5

Odd

Question 6

An even minus and even equals an

Answer 6

Even

Question 7

An odd minus an odd equals an

Answer 7

Even

Question 8

An odd minus an even equals an

Answer 8

Odd

Question 9

An even minus and odd equals an

Answer 9

Odd

Question 10

An even times an even equals an

Answer 10

Even

Question 11

An odd times an odd equals an

Answer 11

Odd

Question 12

An odd times an even equals an

Answer 12

Even

Question 13

Order of operations

Answer 13

Parentheses
Exponents 
Multiplication
Division 
Addition
Subtraction

Question 14

Prime numbers

Answer 14

Have only two divisors, themselves and one

2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97,101,103,107,109

Question 15

Divisor

Answer 15

The number you divide by

Dividend / Divisor = Quotient

Question 16

Greatest common divisor

Answer 16

The greatest common divisor (gcd) of two or more integers, when at least one of them is not zero, is the largest positive integer that divides the numbers without a remainder. For example, the GCD of 8 and 12 is 4.

Question 17

Multiple

Answer 17

A multiple is the product of any quantity and an integer. In other words, for the quantities a and b, we say that b is a multiple of a if b = na for some integer n, which is called the multiplier or coefficient. If a is not zero, this is equivalent to saying that b/a is an integer with no remainder.

If b is a multiple of a then b/a equals an integer with no remainder

Question 18

Greatest common factor

Answer 18

To find either the Least Common Multiple (LCM) or Greatest Common Factor (GCF) of two numbers, you always start out the same way: you find the prime factorizations of the two numbers. Then you put the factors into a nice neat grid of rows and columns, and compare and contrast and take what you need.

Question 19

Least common multiple

Answer 19

It is the smallest number that is a factor of both numbers

The least common multiple has to be divisible by both numbers with a resulting integer

http://www.purplemath.com/modules/lcm_gcf.htm

Question 20

A number is evenly divisible by 2 if

Answer 20

It’s units digit is divisible by 2

Question 21

A number is divisible by 3 if

Answer 21

The sum of its digits is divisible by 3

Question 22

A number is evenly divisible by 4 if

Answer 22

The number made by the tens and units digit is divisible by 4

Question 23

A number is evenly divisible by 5 if

Answer 23

It’s units digit is a 0 or a 5

Question 24

A number is evenly divisible by 6 if

Answer 24

It’s divisible by both 2 and 3

Question 25

A number is evenly divisible by 9 if

Answer 25

The sum of its digits is divisible by 9

Question 26

A number is evenly divisible by 10 if

Answer 26

It's unit digit is a 0

Question 27

Consecutive integers

Answer 27

Integers that follow consecutively

Question 59

Comparing two positive fractions by

Answer 59

Cross multiplying the denominators into the opposite numerator and comparing. The aide with the larger number is greater If the numerators are the same, the smaller denominator is a larger number

Question 60

Decimal Places

Answer 60

Each place in a decimal is worth ten times more than the place to its immediate right

Question 61

Adding and subtracting decimals

Answer 61

Align the decimals and add

Question 62

Multiplying decimals

Answer 62

Multiply as normal and then place decimal the number of digits equivalent to what is to the right of the decimal

Question 63

Dividing decimals

Answer 63

Make divisor a whole number by moving the decimal to the right, then move the decimal of the dividend the same amount

Question 64

Part =

Answer 64

Percent + Whole

Question 65

Percent =

Answer 65

Part / Whole

Question 66

Whole

Answer 66

Part / Percent

Question 67

% increase =

Answer 67

New amount - old amount / old amount x 100

Question 68

% decrease =

Answer 68

Original - new amount / original amount x 100

Question 69

Original price =

Answer 69

New price / 100% - % markdown

Question 70

Original price =

Answer 70

New price / 100% + % markup

Question 71

Inverse proportions

Answer 71

Flip one of the ratios and solve for the missing variable

Question 72

Averaging consecutive integers

Answer 72

The average of a group of consecutive or spaced integers is always at the exact middle number If the number of integers in the group is odd the average is the middle integer If the number of integers in the group is even the middle number is the average of the inner most integers