Paper 1MA1: 1F Question Working Answer Mark Notes 28 Shows M1 forms equation 48÷3 (=16) 3(2x + 6) = 48 or reasoning to eg 2x + 6 = 5x 9 3(5x 9) = 48, condone – – reach missing bracket y=3 M1 isolates and number forms equation 2x+6=“16” Isolates and number x x terms or 5x terms 6x = or 15x = – 9= “16” “30” “75” 3x = 15 M1 side isolates and number terms forms the second equation x substitutes “5” into length 2x= or 5x = “10” “25” eg 2 × 5 + 6 (=16) A1 48÷16=3 or 16×3=48 shows for both solutions from 2 different x=5 x=5 equations. 29 Comment B1 for correct mathematical comment eg line segments not a curve or should draw freehand or should not use a ruler, or should be a curve NB Do not accept statements about scale or plotting accuracy. 30 4 M1 for a complete method eg 2.80 × 100 ÷ oe or 2.80 ÷ 0.7 oe (100−30) or for build up method but must show all intermediate steps unless all figures are correct eg 2.8 ÷ 7 = 0.4 and × 10 (=4) “0.40” A1 cao
Paper 1MA1: 1F Question Working Answer Mark Notes 28 Shows reasoning to reach y=3 M1 forms equation eg 2x + 6 = 5x – 9 48÷3 (=16) 3(2x + 6) = 48 or 3(5x – 9) = 48, condone missing bracket M1 isolates x and number terms 3x = 15 forms equation 2x+6=“16” or 5x – 9= “16” Isolates x and number terms 6x = “30” or 15x = “75” M1 substitutes “5” into side length eg 2 × 5 + 6 (=16) isolates x and number terms 2x= “10” or 5x = “25” forms the second equation A1 48÷16=3 or 16×3=48 shows x=5 for both solutions x=5 from 2 different equations. 29 Comment B1 for correct mathematical comment eg line segments not a curve or should draw freehand or should not use a ruler, or should be a curve NB Do not accept statements about scale or plotting accuracy. 30 4 M1 for a complete method eg 2.80 × 100 ÷ (100−30) oe or 2.80 ÷ 0.7 oe or for build up method but must show all intermediate steps unless all figures are correct eg 2.8 ÷ 7 = 0.4 and “0.40” × 10 (=4) A1 cao
02b_1ma1_1f_-_november_2017_mark_scheme.docx