Maths IGCSE
Are the bars joined together in a histogram or a column (bar) chart? - ANS-A histogram
\Calculate the simple interest on 50,000 if there rate is 5% for 3 years - ANS-I = Prn, I = 50000 *
() * 3
\Compound interest - ANS-I = P * rate^no.of years (I=P*r^n)
\Continuous data - ANS-Data that can be measured (1.7645 m)
\Discrete data - ANS-Data that can be counted (2 cars)
\Helpful tip on ratios. What does the ratio 11 : 9 really mean? - ANS-If two values are in the ratio
11 : 9, it just means that one value divided by the other is equal to .
\How to find the Interquartile Range - ANS-Split data in half and minus the middle value in the
second half from the middle value in the first half! NOT Q3 - Q1 STUFF
\How will the graph of f(x) be different to 2f(x)?
What about the graph of f(2x)? - ANS-2f(x) will be twice as high (y-values doubled)
f(2x) will be narrower
\If a question asks you to simplify, what should you do?
If a question asks you to factorise, what should you do? - ANS-Simplify: opposite of
factorisation, work forwards (multiply out brackets, divide etc.)
Factorise: opposite of simplification, try to group numbers.
\If in a quadratic sequence you have a second difference of 4, what will the coefficient of n^2
be? How about for a second difference of 6, and 8? - ANS-The coefficient will be 2n^2, because
the coefficient is the second difference / 2. If it is the third difference, it would be third difference /
3, the fourth /4, and so on.
\If there is a question on a teacher or somebody else doubting a value obtained from an
equation or line of best fit, why would they doubt the value? - ANS-There is a weak correlation.
\Line of best fit must go through which point? - ANS-(Mean x, mean y)
\Simple interest, how do you get r from a percentage rate? - ANS-Interest = Principal * rate *
number of years
I = Prn
R is percentage rate ÷ 100, e.g. a rate of 6% would have the multiplier 0.06
\What are the two proofs of a cyclic quadrilateral? - ANS-1) opposite angles are supplementary
(180)
2) the exterior angle is equal to the opposite interior angle
\What is 0.00921 in standard form? - ANS-9.21*10^-3. REMEMBER TO PUT MINUS!!!
\What is 2x10^6 X 3x10^3? - ANS-6*10^9, multiply "normal numbers" and add the tenth powers.
\What is 6x10^*10^5? - ANS-2x10^5, first divide 6 by 3, when take 5 away from the 10th
power to get 5th power.
\What is the formula for the period of a trigonometric graph? - ANS-Period = 360 / b, in sin(x) =
sin(b*x)
Are the bars joined together in a histogram or a column (bar) chart? - ANS-A histogram
\Calculate the simple interest on 50,000 if there rate is 5% for 3 years - ANS-I = Prn, I = 50000 *
() * 3
\Compound interest - ANS-I = P * rate^no.of years (I=P*r^n)
\Continuous data - ANS-Data that can be measured (1.7645 m)
\Discrete data - ANS-Data that can be counted (2 cars)
\Helpful tip on ratios. What does the ratio 11 : 9 really mean? - ANS-If two values are in the ratio
11 : 9, it just means that one value divided by the other is equal to .
\How to find the Interquartile Range - ANS-Split data in half and minus the middle value in the
second half from the middle value in the first half! NOT Q3 - Q1 STUFF
\How will the graph of f(x) be different to 2f(x)?
What about the graph of f(2x)? - ANS-2f(x) will be twice as high (y-values doubled)
f(2x) will be narrower
\If a question asks you to simplify, what should you do?
If a question asks you to factorise, what should you do? - ANS-Simplify: opposite of
factorisation, work forwards (multiply out brackets, divide etc.)
Factorise: opposite of simplification, try to group numbers.
\If in a quadratic sequence you have a second difference of 4, what will the coefficient of n^2
be? How about for a second difference of 6, and 8? - ANS-The coefficient will be 2n^2, because
the coefficient is the second difference / 2. If it is the third difference, it would be third difference /
3, the fourth /4, and so on.
\If there is a question on a teacher or somebody else doubting a value obtained from an
equation or line of best fit, why would they doubt the value? - ANS-There is a weak correlation.
\Line of best fit must go through which point? - ANS-(Mean x, mean y)
\Simple interest, how do you get r from a percentage rate? - ANS-Interest = Principal * rate *
number of years
I = Prn
R is percentage rate ÷ 100, e.g. a rate of 6% would have the multiplier 0.06
\What are the two proofs of a cyclic quadrilateral? - ANS-1) opposite angles are supplementary
(180)
2) the exterior angle is equal to the opposite interior angle
\What is 0.00921 in standard form? - ANS-9.21*10^-3. REMEMBER TO PUT MINUS!!!
\What is 2x10^6 X 3x10^3? - ANS-6*10^9, multiply "normal numbers" and add the tenth powers.
\What is 6x10^*10^5? - ANS-2x10^5, first divide 6 by 3, when take 5 away from the 10th
power to get 5th power.
\What is the formula for the period of a trigonometric graph? - ANS-Period = 360 / b, in sin(x) =
sin(b*x)
