001 FOM- Arithmetic Flashcards
Define: integer
A whole number
Express x as a factor of y for some integer n
y=xn
What is another name for factor?
Divisor
What are the quotient and remainder for the following equation?
=28/8
Quotient is 3
Remainder is 4
Express quotient and remainder as a formula. What are the bounds of r?
y = xq+r
0
What are the quotient and remainder when a smaller integer is divided by a larger one?
Q= 0 R = the smaller integer
Y=xq+r
5=7*0+5
Define prime numbers
A positive integer with two different positive divisors, 1 and itself.
What is the smallest prime number?
2
Express consecutive integers as an equation
N, n+1, n+2, n+3…where n is an integer
Express consecutive even integers as an equation
2n, 2n+2, 2n+4…
Define least common multiple
The smallest common multiple of two numbers
How do you divide by a fraction?
Invert the divisor (ie take the reciprocal of the fraction) and multiply
Define a mixed number.
A number consisting of a whole number and a fraction
How to change a mixed number into a fraction?
Multiple the whole number by the denominator and add to the numerator
7 2/3 = 23/3
Express 0.0321 as a fraction
0/10 + 3/100+2/1000+1/10,000
= 321/10,000
lcm is 10,000
How to multiply decimals?
Multiply the numbers as whole numbers. Insert the decimal so that the number of digits to the right is equal to the sum of the numbers of digits to the right of the decimal points in the numbers being multiplied.
2.09 x 1.3 = 627+2090= 2.717
How to divide decimals?
Move the decimal point of the divisor to the right until it’s a whole number. Move the decimal of the dividend the same number. Divide. Put the decimal in the quotient directly above the decimal in the new dividend.
12.4[698.12
=124[6981.2
=56.3
Express xy+xz alternatively
X(y+z)
Define proportion re ratios
Statement that two ratios are equal
How can you find the % increase?
1) find amount of increase
2) divide increase by original amount
3) express as a %
How does the % increase from x to y compare to a % decrease from y to x?
Decrease will be a smaller %, as it is the same amount of change, but the comparable is a larger number
What happens when you square a number between 0 and 1?
It gets smaller
1/3 squared = 1/9
How many square roots does a positive number have?
Two: one positive and the other negative
How many cube roots does a real number have
One
Define mean
The average
Define median
Center for a list of numbers (which are in order from least to greatest). If there are an even amount of numbers, the median is the average of the two middle numbers
What is the relationship between median and mean?
None. Median can be less, equal or more.
Define mode
The number occurring most frequently in a lost. Can be multiple modes for a given list.
What values influence standard deviation most?
Those farthest from the mean. The closer data is grouped around the mean, the smaller the SD
How to calculate standard deviation?
1) calculate mean of x numbers
2) calc each diff from mean (x-mean)
3) square each diff
4) calc mean of squared diff
5) find positive square root of this mean
How to determine mean using frequency distribution?
1) multiply each data value by its frequency
2) sum the results
3) divide by the number of data values
What is union of any two sets A and B?
The set of all elements that are in set A or B or both. represented by a capital U
What is the intersection of sets A and B?
The set of all elements that are both in A and B. Represented by the shaded part of a Venn diagram or an inverted U
Express the Union of two sets mathematically
s U t = set s + set t - Intersection s and t
What is the factorial of n?
n!
Defined as the product of all integers from 1 to n.
4! = 123*4=24
Define permutation and express as a formula
A selection process in which objects are selected one by one in a certain order. Represents all the ways the objects can be ordered.
For a set of n objects:
n(n-1)(n-2) =n!
Formula for a set of n objects from which a complete selection of k objects is to be made without regard to order, where 0
N
K
=
N!/k!(n-k)!
Probabilities are between what range?
0 (impossible) to 1 (certain)
Express probability as a formula
Number of outcomes in E/total number of possible outcomes.
Where E represents a possible event
What is the probability of event E and event F happening, where E and F are independent events?
What is this called?
P(E)*P(F)
Intersection
What is the probability of E or F happening, where E and F are independent? What is this called?
= P(E)+P(F)-P(E and F)
Called the union
What are alternative ways of saying 15 is divisible by 3?
1) 15 is a multiple of 3
2) 3 is a factor of 15
3) 3 goes into 15
4) 3 divides 15
Is zero even or odd? Why?
Even, because it is divisible by 2 (0/2 = 0)
What is the number underneath an exponent?
The base
What does a root do to an exponent?
Undoes it