Quantitative Reasoning Flashcards
Mean
Average. Add up all the values and divide the total by how many there are
Median
Middle number of a set of data.
Order numerically
Mode
Number that occurs most often in a set
Range
Difference between highest and lowest
Rate problems
When 2 things travel towards each other, we need to add the 2 velocities together .
E.g. Train 1 going east 50mph and train going west 40mph. They are 135 miles apart. How long before they collide?
t = 135miles/(40mph+50mph) = 135/90 = 1.5 hours
Dice problems
Rolling 2 dice - Total no. of permutations = 36
E.g. What is the probability of rolling 2 dice and having the 2 numbers add up to 4?
Three possibilities - 2+2, 1+3, 3+1
Therefore probability - 3/36 = 1/12
Deck of cards
Total number of cards = 52 (Without jokers)
4 Suits (Heart, club, ace, diamond)
13 cards per suit
With replacement: Total number of cards must go back to 52 and cards of interest must go back to initial amount.
Without replacement: Must decrease total number of cards by 1 and decrease number of cards of interest by 1.
E.g. Probability of pulling 3 spades in a deck without replacement?
13/52 * 12/51 * 11/50 = 33/2550
Speed formula
Speed = distance/time
Acceleration formula
Acceleration = Change in velocity/time
Slope formula
y = mx+c. M=gradient, C= Y-intercept
Area of a circle
πr^2 r=radius
Circumference of a circle
πd d=diameter (2*radius)
Area of a triangle
1/2 * base * height
Volume of sphere
(4/3)πr^3
Volume of a cylinder
πr^2 * h
1/20
0.05 = 5%
1/10
0.1 = 10%
1/9
0.11 = 11%
1/8
0.125 = 12.5%
1/7
0.14 = 14%
1/6
0.17 = 17%
