Maths revision Flashcards
(42 cards)
What is the nth term of this sequence? 2, 9, 16, 23, 30”
7n - 5
What is the formula for the total interior angles of a polygon?
(n - 2) x 180
What are the first four cube numbers?
1, 8, 27, 64
You are given a right angled triangle and the lengths of the two short sides. How do you find the hypotenuse?
Pythagoras: a squared plus b squared = c squared
How would you calculate the area of a 48º sector of a circle?
πr squared x 48 ÷ 360
What two things do you need to specify for an enlargement?
- Centre of enlargement 2. Scale factor
What is the formula for frequency density on a histogram?
frequency density = frequency ÷ class width
What does 81 to the power of 1⁄2 mean?
Square root of 81 (= 9)
What does 3 to the power of -2 mean?
One over 3 squared (= one ninth)
How would you increase £350 by 14%?
350 x 1.14 (100% + 14%)
How would you decrease 465g by 35%?
465 x 0.65 (100% - 35%)
What is an integer?
A whole number (can be positive or negative)
Which of these fractions produce terminating (non-recurring) decimals?
3/20, 2/7, 5/8, 2/3
3/20 and 5/8 - the ones where the only prime factors of the denominator are 2 and/or 5
Express 48 as the product of prime factors
2 x 2 x 2 x 2 x 3 (can do on the calculator with 48, =,
shift, factor)
What is the formula for ‘y is directly proportional to x’?
y = kx
What is the formula for ‘y is inversely proportional to x’?
y = k/x
if two triangles are ‘similar’ what is the same about them?
the angles
How do you find the linear scale factor for similar shapes?
Find the matching pair, divide one by the other
What is 458.35 correct to two significant figures?
460
Factorise ‘x squared - 64’
(x + 8)(x - 8) This is the ‘difference of two squares’
Express this recurring decimal as a fraction: 0.27272727…
27/99
f(x) = 2x + 1. What is the inverse function?
(x - 1) ÷ 2
What is the sum of the exterior angles of a polygon?
360º
What is each exterior angle of a regular 10-sided polygon?
360º ÷ 10 = 36º