Forming Equations: WJEC GCSE Intermediate June 2017 Unit 1 Q19

Intermediate June 2017 Unit 1 Q19

19. Rashid owned \(n\) sheep.
Eifion had exactly 4 times as many sheep as Rashid.

Rashid buys 17 extra sheep.
Eifion sells 8 of his sheep.

Eifion still has more sheep than Rashid.

Form an inequality, in terms of \(n\).
Solve the inequality to find the least value of \(n\).
You must show all your working. [5]

Mark scheme

Scheme	Marks	Comments
\(4n - 8 > n + 17\)	B2	If not B2, allow B1 for sight of \(4n - 8\) AND \(n + 17\) in an inequality.
\(3n > 25\)	B1	F.T. from ‘their inequality’, if of equivalent difficulty.
\(n > 25/3\)	B1	F.T. from ‘their an>b’ or ‘their an<b’ provided a≠1.
(least value of \(n\) =) 9	B1	F.T. from their ‘\(n\) > 25/3’, provided n > 0. An answer of 9 without showing 4n - 8 > n + 17 gains B3 only. Accept ‘Rashid had 9 (sheep)’.