Foundation November 2022 Paper 3 Q10

OCRFoundationCurrent spec6 marksDecimals Percentages

10 Two supermarkets, A and B, have special offers on the same packet of biscuits.

Supermarket A	Supermarket B
Normal price: £1.50 for each packet Special offer: Buy two packets at the normal price and get a third packet for half price	Normal price: £1.60 for each packet Special offer: 10% off the normal price

(a) Dan buys one packet of these biscuits.

Which supermarket is best value for Dan?
Show how you decide.

Supermarket .................... because ........................................ [3]

(b) Darcy buys three packets of these biscuits.

Which supermarket is best value for Darcy?
Show how you decide.

Supermarket .................... because ........................................ [3]

Mark scheme (a)

Answer	Marks	Part marks and guidance
B and 1.44 is less than 1.5[0] oe or B and ([0].06 or 6p) cheaper oe or B and 1.44 and 1.5[0] seen in final statement	3	M2 for \(1.6[0] \times 0.9\) oe implied by 1.44 or M1 for \(1.6[0] \times 0.1\) oe implied by [0].16	Allow B and “It’s cheaper oe” if only 1.44 [and 1.50] seen in working space Accept all figures in pence May be \(1.6[0] - 1.6[0] \times 0.1\) oe M0 for 10% of 1.6[0] See Appendix B and 3.75 and 4.32 only scores 0 B and 1.44 and 3.75 scores M2 only

Appendix for 10a

Working and answer	Mark	Reason
3.75 and 4.32 seen in working Answer: B it is cheaper because 1.44 is cheaper than 1.5	3	Answer uses correct figures
1.44 only seen in working Answer: B it costs less	3	There can be no other figure to compare with so all marks awarded
1.44, 3.75 and 4.32 seen in working Answer: B He only wants one packet so it is cheaper	M2	M2 for 1.44 but no comparison
1.44 and 3.75 seen in working Answer: B even when you buy 2 packets it is cheaper than A	M2	M2 for 1.44 but no comparison
Answer: B and 1.44 cheaper than 3.75	M2	Answer based on incorrect figures but 1.44 seen
16p found and 3.75 seen Answer: B and 3.59 cheaper	M1	16p seen but 3.59 comes from 3.75 – 0.16 so incorrect values. M1 as 16p used
Answer: B and 3.75 lower than 4.32	0	Answer based on incorrect values

Mark scheme (b)

Answer	Marks	Part marks and guidance
A and 3.75 less than 4.32 oe or A and [0].57 saved oe or A and 3.75 and 4.32 seen in final statement OR A and 1.25 less than 1.44 oe or A and 0.19 oe saved or A and 1.25 and 1.44 seen in final statement	3	Method 1 M1 for \(1.5 \times 2.5\) oe or 3.75 oe M1 for their \(1.44 \times 3\) or \((3 \times 1.6) \times 0.9\) oe or 4.32 oe Method 2 M2 for \(1.5 \times 2.5 \div 3\) oe or 1.25 or M1 for \(1.5 \times 2.5\) oe or 3.75	Ignore other figures/statements that don’t invalidate answer All values may be seen in (a) oe may be \(1.5 + 1.5 + 1.5 \div 2\) Allow “A because it’s cheaper” oe if 3.75 and 4.32 only seen as final costs in working space for (b) Allow “A because it’s cheaper” oe if 1.25 and 1.44 only seen as final costs in working space for (b)