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Getting Pupils to Rich Mark. Why do it …. How to do it …. Non-Calculator Feedback (10N2). If you divide by a number that is 100 times smaller, your answer will be 100 times greater To work out three quarters, divide by 4 and multiply by 3
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Why do it … How to do it …
Non-Calculator Feedback (10N2) • If you divide by a number that is 100 times smaller, your answer will be 100 times greater • To work out three quarters, divide by 4 and multiply by 3 3b) When factorising into one bracket, make sure to take a number and letter out where possible 3d) Always check the signs when expanding brackets 5) To estimate remember to round all numbers to 1 significant figure first 6) If you know the sale price and want the normal price decide what you would have multiplied to decrease it and then do the reverse 8a) Always check whether algebraic fractions are being added or subtracted otherwise you will expand the bracket incorrectly 8b) When simplifying algebraic fractions factorise numerator and denominator and cancel anything which is the same
Assessment 1 feedback (11A5) • Make sure you round to 1 significant figure and not one to 1 decimal place • For ratio check whether you have the total which needs to be split or if you already know one of the amounts • Use a two way table to analyse information where two categories are investigated • To compare best value work out the price of one item and do not round your answers • To work out if a term is in a sequence, put the n’th term rule equal to the term and solve the equation. If a whole number then yes, it is in the sequence 10) To work out what one number is a percentage of another, divide the amount by the total and multiply by 100 • When dividing indices, subtract indices • Circumference = Pi x diameter 14a) Modal class is the group with the highest frequency 14b) To estimate the mean from a grouped frequency table use (midpoint x freq) ÷ by total frequency 14c) To plot a frequency polygon, plot in the middle of the interval and join with straight lines • When you know two sides of a right angled triangle and are working out the third, use Pythagoras. If you are working out c, you need to use c2 = a2 + b2 19b) When writing a number in standard form, the multiplier must be between 1 and 10 23) To decide on a stratified sample use (group ÷ total) x sample size 27) To interpret a histogram use frequency = frequency density x class width