M1.          Award TWO marks for the correct answer of 67
If the answer is incorrect, award ONE mark for evidence of an appropriate method, eg
          7 gaps = 77
1 gap = 11
Answer need not be obtained for the award of the mark.
Up to 2
[2]

 

M2.         Indicates the answer could be positive or negative and gives a correct explanation
eg 
•      A positive multiplied by −5 gives a negative answer, but a negative multiplied by −5 gives a positive answer 
•      Positive numbers will become negative, negative numbers will become positive
•      If the number is 10 the answer will be –50, which is negative, but if the number is −10, the answer is 50, ie positive 
Accept minimally acceptable explanation eg •      10 becomes negative, but −10 becomes positive •      +ve → –ve        –ve → +ve •     −5 × −3 = 15, −5 × 3 = −15 
Do not accept incomplete explanation eg •      –5 × 3 = −15 •      The original number could be positive or negative so the answer could be positive or negative
! Makes an incorrect decision, or no decision made, but explanation clearly correct Condone provided the explanation is more than minimal
U1
[1]