Quantitative Reasoning Flashcards
distance = ?
distance = speed x time
speed = ?
speed = distance/time
time = ?
time = distance/speed
upstream speed = ?
upstream speed = distance/time upstream
downstream speed = ?
downstream speed = distance/time downstream
speed of stream = ?
speed of stream = downstream speed - upstream speed / 2
speed of boat in stillwater = ?
speed of boat in stillwater = (downstream speed + upstream speed) / 2
average speed of boat = ?
average speed of boat = downstream speed x upstream speed / (downstream speed + upstream speed / 2)
relative speed (moving towards each other) = ?
relative speed (moving towards each other) = speed of object 1 + speed of object 2
relative speed (moving in the same direction) = ?
relative speed (moving in the same direction) = speed of faster object - speed of slower object
time taken = ?
time taken = work done/rate of work
work done = ?
work done = time taken x rate of work
rate of work = ?
rate of work = work done/time taken
% = ?
% = (part/whole) x 100
part = ?
part = (%/100) x whole
whole = ?
whole = part / (%/100)
% increase = ?
% increase = (new value - old value / old value) x 100
% decrease = ?
% decrease = (old value - new value / old value) x 100
“decrease %: old minus new over old times 100”
Price = ?
Price = (no. of items)(cost per item)
Sale price = ?
(price at which an item is sold)
Sale price = Cost price (1 + Profit %/100)
Sale price = ?
Sale price = Cost price (1 - Loss %/100)
Profit = ?
Profit = Sale price - Cost price
Loss = ?
Loss = Cost price - Sale price
Profit % = ?
Profit % = (Profit/CP) x 100
Loss % = ?
Loss % = (Loss/CP) x 100
Principal = ?
Principal = (SI × 100) / RT
Rate of interest = ?
Rate of interest = (SI × 100) / PT
Time = ?
Time = (SI × 100) / PR
Simple interest = ?
Simple interest = PRT/100 or Total Amount (A) - Principal (P)
Amount after interest (A) = ?
Amount after interest (A) = Principal (P) + Simple Interest (SI)
Compound interest = ?
Compound interest = A - P
Amount after compound interest (A) = ?
Amount after compound interest (A) = P (1 + R/100) ^T
Compound interest (n no. of times)= ?
Compound interest = P (1 + R/n) ^n^T - P
Compound interest (half-yearly)= ?
Compound interest (half-yearly)= P [1 + (R/2)/100]^2T - P
Principal (of CI) = ?
Principal = A/(1 + R/100)^T
Area of square = ?
Area of square (diagonals) = ?
Perimeter of square = ?
Area of square = a^2
Area of square (diagonals) = 1/2 diagonal^2
Perimeter of square = 4a
Area of rectangle = ?
Perimeter of rectangle = ?
d² = ?
L = ?
Area of rectangle = LW
Perimeter of rectangle = 2(L+W)
d² = L² + W²
L = Area/W
Area of triangle = ?
Perimeter of triangle = ?
Area of triangle = 1/2 bh
Perimeter of triangle = sum of all sides
Area of parallelogram = ?
Perimeter of parallelogram = ?
Area of parallelogram = bh
Perimeter of parallelogram = 2 (base + side) | 2 (b + a)
Area of rhombus = ?
Perimeter of rhombus = ?
a = ?
Area of rhombus = 1/2 (diagonal1)(diagonal2)
Perimeter of rhombus = 4a
a = √(diagonal1/2)² + (diagonal2/2)²
Area of trapezoid = ?
Perimeter of trapezoid = ?
Area of trapezoid = 1/2 (a + b; sum of parallel sides)(h; perpendicular distance between the sides) | 1/2 (a + b)(h)
Perimeter of trapezoid = (a + b + c + d; sum of all sides)
Area of circle = ?
Circumference = ?
Diameter = ?
r = ?
distance = ?
midpoint = ?
Area of circle = πr²
Circumference = 2πr
Diameter = 2r
r = Diameter/2
distance = √(x2 - x1)² + (y2 - y1)²
midpoint = (x1+x2/2 , y1+y2/2) = (h, k)
equation of the circle = ?
equation of the circle = (x-h)² + (y-k)² = r²
Cube surface area = ?
Cube volume = ?
Diagonal = ?
Cube surface area = 6a²
Cube volume = a³
Diagonal = a√3
Rectangle/cuboid surface area = ?
Rectangle/cuboid volume = ?
Diagonal = ?
Rectangle/cuboid surface area = 2(LW+WH+HL)
Rectangle/cuboid volume = LWH
Diagonal = √L²+W²+H²
Cylinder surface area = ?
Cylinder volume = ?
Cylinder surface area = 2πr² + 2πrh
Cylinder volume = πr²h
Sphere surface area = ?
Sphere volume = ?
Sphere surface area = 4πr²
Sphere volume = 4/3πr³
Cone total surface area = ?
Cone curved surface area = ?
Slant height = ?
Cone volume = ?
Cone total surface area = πr² + πrl
• r = radius of the base of the cone
• l = slant height of the cone
Cone curved surface area = πrl
Slant height (l): l² = r² + h²
Cone volume = 1/3πr²h
Pyramid surface area = ?
Pyramid volume = ?
Pyramid surface area =
Pyramid volume = 1/3 (base area)(h)
Coordinate
Distance = ?
Midpoint = ?
Slope (m) = ?
Slope intercept form: ?
Point-slope form: ?
Distance = √[(x₂ - x₁)² + (y₂ - y₁)²]
Midpoint = [(x₁ + x₂)/2, (y₁ + y₂)/2]
Slope (m) = (y₂ - y₁)/(x₂ - x₁)
Slope intercept form: y = mx + b
Point-slope form: y - y₁ = m(x - x₁)
sin x = ?
cos x = ?
tan x = ?
sec x = ?
csc x = ?
cot x = ?
SOH sin x = opp/hyp
CAH cos x = adj/hyp
TOA tan x = opp/adj
SHA sec x = hyp/adj
CHO csc x = hyp/opp
CAH cot x = adj/hyp
Pythagorean identities
(fundamental trigonometric identities derived from the Pythagorean theorem; they relate the squares of sine, cosine, and tangent)
• ? + ? = 1
• 1 + ? = sec² x
• 1 + ? = csc² x
• sin² x + cos² x = 1
• 1 + tan² x = sec² x
• 1 + cot² x = csc² x
Reciprocal identities
sin x = 1/csc x
cos x = 1/sec x
tan x = 1/cot x
csc x = 1/sin x
sec x = 1/cos x
cot x = 1/tan x
Quotient identities
(relate the tangent and cotangent functions to sine and cosine)
• tan x = ____/cos x
• cot x = ____/sin x
• tan x = sin x/cos x
• cot x = cos x/sin x
Cofunction identities
[show the relationship between trigonometric functions of complementary angles (angles that add up to 90° or π/2)]
• sin (90° - x) = cos x, cos (90° - x) = sin x
• tan (90° - x) = cot x, cot (90° - x) = tan x
• sec (90° - x) = csc x, csc (90° - x) = sec x
Sum and difference formulas
(allow you to calculate the sine, cosine, and tangent of the sum or difference of two angles)
• sin (A+B) = ?
• sin (A-B) = ?
• cos (A+B) = ?
• cos (A-B) = ?
• tan (A+B) = ?
• tan (A-B) = ?
• sin (A+B) = sinAcosB + cosAsinB
• sin (A-B) = sinAcosB - cosAsinB
• cos (A+B) = cosAcosB - sinAsinB
• cos (A-B) = cosAcosB + sinAsinB
• tan (A+B) = (tanA + tanB)/(1 - tanAtanB)
• tan (A-B) = (tanA - tanB)/(1 + tanAtanB)
Double angle formulas
• sin (2x) = 2sinx____
• cos (2x) = cos²x - _____
• cos (2x) = ______ - 1
• cos (2x) = 1 - ______
• tan (2x) = 2tanx/(1 - _____)
• sin (2x) = 2sinxcosx
• cos (2x) = cos²x - sin²x
• cos (2x) = 2cos²x - 1
• cos (2x) = 1 - 2sin²x
• tan (2x) = 2tanx/(1 - tan²x)
Half angle formulas
• sin (x/2) = ±√[(1 - ____) / 2]
• cos (x/2) = ±√[(1 + ____) / 2]
• tan (x/2) = ±√[(1 - ____) / (1 + ____)]
• tan (x/2) = ____ / (1 + cosx)
• tan (x/2) = (1 - ____) / ____
• sin (x/2) = ±√[(1 - cosx) / 2]
• cos (x/2) = ±√[(1 + cosx) / 2]
• tan (x/2) = ±√[(1 - cosx) / (1 + cosx)]
• tan (x/2) = sinx / (1 + cosx)
• tan (x/2) = (1 - cosx) / sinx
*The ± sign depends on the quadrant in which x/2 lies: ASTC rule (All Students Take Calculus) to determine the sign of each function based on the quadrant.
A (All): In QI, all trigonometric functions (sin, cos, tan, and their reciprocals) are positive.
S (Sine): In QII, only sin and its reciprocal csc are positive. All others are negative.
T (Tangent): In QIII, only tan and its reciprocal cot are positive. All others are negative.
C (Cosine): In QIV, only cos and its reciprocal sec are positive. All others are negative.
Diagram Representation
1st Quadrant (0° to 90°): All positive
2nd Quadrant (90° to 180°): Sine positive
3rd Quadrant (180° to 270°): Tangent positive
4th Quadrant (270° to 360°): Cosine positive
Product to sum formulas
(used to rewrite the product of sine and cosine functions as a sum or difference of trigonometric functions)
Product of sines and cosines
sinAcosB = ?
Product of cosines and sines
cosAsinB = ?
Product of cosines
cosAcosB = ?
Product of sines
sinAsinB = ?
Product of sines and cosines
sinAcosB = (1/2) [ sin(A + B) + sin(A - B) ]
Product of cosines and sines
cosAsinB = (1/2) [ sin(A + B) - sin(A - B) ]
Product of cosines
cosAcosB = (1/2) [ cos(A + B) + cos(A - B) ]
Product of sines
sinAsinB = (1/2) [ cos(A - B) - cos(A + B) ]
Sum to product formulas
(used to rewrite the sum or difference of trigonometric functions as a product)
• sin(A) + sin(B) = ?
• sin(A) - sin(B) = ?
• cos(A) + cos(B) = ?
• cos(A) - cos(B) = ?
• sin(A) + sin(B) = 2sin[(A + B)/2] cos[(A - B)/2]
• sin(A) - sin(B) = 2cos[(A + B)/2] sin[(A - B)/2]
*pos: sin-cos, neg: cos-sin
• cos(A) + cos(B) = 2cos[(A + B)/2] cos[(A - B)/2]
• cos(A) - cos(B) = -2sin[(A + B)/2] sin[(A - B)/2]
*pos: cos-cos, neg: sin-sin
maximum value
sin (x) = ?
cos (x) = ?
minimum value
sin (x) = ?
cos (x) = ?
maximum value
sin (x) = 1
cos (x) = 1
minimum value
sin (x) = -1
cos (x) = -1
Maximum and mnimum values
R = ?
R = √A² + B²
1 kg = ? g
1000 g
1 mi = ? km
1.609344 km
1️⃣▪️6️⃣0️⃣9️⃣3️⃣4️⃣4️⃣
1 L = ? gallons
0.2641720524 gallons
0-264-172-0524
1 in = ? cm
2.54 cm
1 ft = ? in
12 in
1 m = ? cm
100 cm
1 km/h = ? m/s
5/18 m/s
m/s to km/h?
18/5 km/h
Radians = ?
Radians = Degrees × π/180