Arithmetic Mastery Flashcards
Rule of Divisibility (3)
3: If the sum of the digits is divisible by 3, the entire integer is a multiple of 3.
Rule of Divisibility (6)
6: If the number is both divisible by 2 and 3, it is divisible by 6.
Decimal Equivalent: 2/3
0.66 (repeating)
Even x Odd =
Even
Decimal Equivalent: 1/6
0.2
Divisible
Describes a number capable of being divided without a remainder. A number that is divisible by x is also said to be a multiple of x. • 18 is divisible by 1, 2, 3, 6, 9, and 18
How do you represent the phrase “what percent”?
How do you represent “minus,” “less than,” “subtracted from,” “decreased by,” “reduced by,” and “difference?”
-
What is the formula for average rate of speed?
Decimal Equivalent: 1/3
0.33 (repeating)
Even x Even =
Even
Common Factor
A factor shared by two numbers • Factors of 18 are 1 and 18, 2 and 9, and 3 and 6. • Factors of 15 are 1 and 15 and 3 and 5. • The common factors of 15 and 18 are 1 and 3.
Rule of Divisibility (4)
4: If the last two digits are a multiple of 4, the entire number is a multiple of 4.
Odd x Odd =
Odd
Odd + Odd =
Even
How do you represent “of,” “times,” or “product?”
X
First 10 Prime Numbers
{2, 3, 5, 7, 11, 13, 17, 19, 23, 29, …}
Rule of Divisibility (2)
2: If the last digit of a number is even, it is a multiple of 2.
How do you represent “per,” “out of,” or “quotient?”
÷
Prime Factor
Prime numbers that divide into a larger number without a remainder • Factors of 18 are 1 and 18, 2 and 9, and 3 and 6; the prime factors are 2 and 3
Even + Odd =
Odd
How do you represent “plus,” “more than,” “added to,” “increased by,” and “sum?”
+
Rule of Divisibility (5)
5: If the last digit ends in 0 or 5, the entire number is divisible by 5.
How do you represent “What” or “What number”?
variable
Decimal Equivalent: 1/5
0.166 (repeating)
Decimal Equivalent: 1/8
0.125
Decimal Equivalent: 1/2
0.5
Even + Even =
Even
All Prime Numbers under 100
{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}
Prime Number
An integer that does not have any factors besides itself and 1
Decimal Equivalent: 1/3
0.33 (repeating)
Rule of Divisibility (9)
9: If the sum of the digits is divisible by 9, the entire integer is a multiple of 9
Decimal Equivalent: 3/4
0.75
What is the rate formula?
What is the formula for combined work problems?
How do you represent “is,” “equals,” or “result?”
=
Decimal Equivalent: 2/5
0.4
Mulitples
An integer that is divisible by another integer without a remainder. (Ex. multiples of 3 include: -3, 3, 6, 9, 12…)
Decimal Equivalent: 1/4
0.25
