SEPARATE ANSWER KEY & DETAILED EXPLANATIONS Below are the comprehensive solutions, step-by-step mathematical workings, and grammatical/literary explanations for all 30 questions. Q#
Ans
Topic / Skill
Step-by-Step Explanation & Method
Q1
C
Percentages
10% of £80 = £8. 5% of £80 = £4. 15% reduction = £8 + £4 = £12. New sale price = £80 - £12 = £68.
Q2
D
Percentages
10% of 30 pupils = 3 pupils. 60% = 6 × 3 = 18 pupils.
Q3
B
Percentages
To express 18 out of 25 as a percentage, multiply numerator and denominator by 4 to get a fraction out of 100: (18 × 4) / (25 × 4) = 72 / 100 = 72%.
Q4
A
Numbers
Prime numbers in order: 2, 3, 5, 7... The 4th prime number is 7. Square root of 81 = √81 = 9. Difference = 9 - 7 = 2.
Q5
C
Numbers (LCM)
Find the Lowest Common Multiple (LCM) of 6 and 8: Multiples of 6: 6, 12, 18, 24, 30... Multiples of 8: 8, 16, 24, 32... LCM = 24 seconds. Next flash time = 10:00:00 + 24 seconds = 10:00:24.
Q6
B
Numbers (BODMAS)
Follow BODMAS order of operations: 1. Brackets: (12 - 7) = 5. 2. Exponents: 52 = 25. 3. Multiplication/Division: 4 × 5 ÷ 2 = 20 ÷ 2 = 10. 4. Addition: 25 + 10 = 35.
Q7
C
Ratio
Q8
D
Ratio
Bexley 11+ Practice Paper
Ratio Orange : Water = 3 : 2. 3 parts = 450 ml ⇒ 1 part = 450 ÷ 3 = 150 ml. Water needed = 2 parts = 2 × 150 ml = 300 ml.