I just took a look at those questions:
If a scarf costs £11.70 after a 10% reduction,
what was the original price? (L1) ( I am not sure if reverse percentage is on Foundation Maths)
Mike’s lunch contains 640 calories of energy.
What percentage is this of his target daily intake of
2000 calories? (L1)
Rail tickets increased by 2% in year 1, and 5% in year 2. What was the overall increase over the two years? (L2)
That's quite a hard one - you don't have a number to start with - so you could start at £100. Then work out 2% of £100. Then work out 5% of £102 and work out the percentage compared to £100
These are three offers on the same ketchup.
Which is the best value for money? (L2)
• 275g for £1.05
• 454g for £1.99
• 650g for £2.20
• 425g: buy two for £3.10
You buy a laptop that costs £899, including VAT at 20%. How much of the purchase price is VAT? (L2)
So you need to do reverse percentage again.
Those aren't the easiest examples to show how numerate people are.
And their conclusion - based on these 5 questions
A fifth of the working-age population has the numeracy level equivalent to a GSCE pass (Grade 4) Based on results from a multiple-choice test of people’s everyday maths skills, 20% of the population scored 4 or 5, roughly equivalent to a GCSE pass (Grade 4 / C). This is in line with the last Government-commissioned Skills for Life survey.
I would suggest that the people who commissioned this survey look at how hard it is to draw conclusions from 5 questions.