Numbers

Question	Answer
Percentage Change: Change/original x 100	percentage profit: profit/original x 100
Finding Ratio Amounts: 1. Add up the parts 2. Find the amount for 'one' part 3. Multiply the answer of 2 by the amount of parts	finding x% of y: e.g. find 15% of £46 0.15 x 46 = £6.90
Express x as a percentage of y e.g. Give 40p as a percentage of 3.34 (40 / 334) x 100 = 12%	percentages: amount x multiplier(to the power of the amount of years)
if you want to know an amount before a certain percentage was added you divide the amount by the multiplier of the amount we have at the start	How To Find Prime Numbers 1. It must end in either 1,3,7,9 2. It won't divide by any of the primes below it's square root
HCF - the biggest number that will divide by all the numbers in the question	LCM - the smallest number that will divide by all the numbers in the question
The Factors of a number are all the numbers that divide into it	The multiples of a number are simply it's timetable
irrational numbers: NEVER ENDING NON RECURRING DECIMAL (e.g. most square and cube roots)	rational numbers: positive or negative a fraction a terminating or recurring decimal

Resource summary

	Created by lydiarutherford about 11 years ago