Mixed Topic Worksheet Grades 6/7: Day 023
- 1
Question 1. Is ≤ft(dfrac12)⁻³ greater than ≤ft(dfrac13)⁻²? You must show your working.
Fractions with Negative Powers▶ Show worked answerHide worked answer
- M1: 2³ = 8 and 3² = 9
- A1: No, 9 is greater
Answer: No. ≤ft(dfrac12)⁻³ = 8 and ≤ft(dfrac13)⁻² = 9[2 marks] - 2
Question 2. Prove that 5(n + 3)² - 5(n + 1)² is a multiple of 20 for all integer values of n.
Proof with Multiples▶ Show worked answerHide worked answer
- M1: 5(n² + 6n + 9) - 5(n² + 2n + 1)
- M1: 20n + 40
- C1: 20n + 40 = 20(n + 2), which is a multiple of 20
Answer: 20(n + 2), a multiple of 20[3 marks] - 3
Question 3. A scientist catches 60 fish in a lake, puts a tag on each fish and returns them to the lake.
A week later she catches 40 fish from the same lake. 8 of these 40 fish have a tag.
Work out an estimate for the number of fish in the lake.Capture-Recapture▶ Show worked answerHide worked answer
- M1: 60 ÷ N = 8 ÷ 40
- M1: 60 × 40 ÷ 8
- A1: 300
Answer: 300[3 marks] - 4
Question 4. Here is triangle XYZ.
Sam wants to work out the length x.
Should Sam use the sine rule or the cosine rule?
Give a reason for your answer.Combining the Sine Rule with Other Rules▶ Show worked answerHide worked answer
- B1: the cosine rule
- B1: two sides and the angle between them are given, and the side opposite that angle is unknown
Answer: The cosine rule, because two sides and the angle between them are given[2 marks] - 5
Question 5. f(x) = 2x + 1
g(x) = x - 9
fg(a) = 15
Work out the value of aComposite Functions▶ Show worked answerHide worked answer
- M1: 2(a - 9) + 1 = 15
- M1: a - 9 = 7
- A1: a = 16
Answer: 16[3 marks]
Mixed Topic Worksheet Grades 6/7: Day 023
- 1
Question 1. Is ≤ft(dfrac12)⁻³ greater than ≤ft(dfrac13)⁻²? You must show your working.
[2 marks]Fractions with Negative Powers▶ Show worked answerHide worked answer
- M1: 2³ = 8 and 3² = 9
- A1: No, 9 is greater
Answer: No. ≤ft(dfrac12)⁻³ = 8 and ≤ft(dfrac13)⁻² = 9 - 2
Question 2. Prove that 5(n + 3)² - 5(n + 1)² is a multiple of 20 for all integer values of n.
[3 marks]Proof with Multiples▶ Show worked answerHide worked answer
- M1: 5(n² + 6n + 9) - 5(n² + 2n + 1)
- M1: 20n + 40
- C1: 20n + 40 = 20(n + 2), which is a multiple of 20
Answer: 20(n + 2), a multiple of 20 - 3
Question 3. A scientist catches 60 fish in a lake, puts a tag on each fish and returns them to the lake.
[3 marks]
A week later she catches 40 fish from the same lake. 8 of these 40 fish have a tag.
Work out an estimate for the number of fish in the lake.Capture-Recapture▶ Show worked answerHide worked answer
- M1: 60 ÷ N = 8 ÷ 40
- M1: 60 × 40 ÷ 8
- A1: 300
Answer: 300 - 4
Question 4. Here is triangle XYZ.
[2 marks]
Sam wants to work out the length x.
Should Sam use the sine rule or the cosine rule?
Give a reason for your answer.Combining the Sine Rule with Other Rules▶ Show worked answerHide worked answer
- B1: the cosine rule
- B1: two sides and the angle between them are given, and the side opposite that angle is unknown
Answer: The cosine rule, because two sides and the angle between them are given - 5
Question 5. f(x) = 2x + 1
[3 marks]
g(x) = x - 9
fg(a) = 15
Work out the value of aComposite Functions▶ Show worked answerHide worked answer
- M1: 2(a - 9) + 1 = 15
- M1: a - 9 = 7
- A1: a = 16
Answer: 16
Mixed Topic Worksheet Grades 6/7: Day 023
- 1
Question 1. Is ≤ft(dfrac12)⁻³ greater than ≤ft(dfrac13)⁻²? You must show your working.
Fractions with Negative Powers▶ Show worked answerHide worked answer
- M1: 2³ = 8 and 3² = 9
- A1: No, 9 is greater
Answer: No. ≤ft(dfrac12)⁻³ = 8 and ≤ft(dfrac13)⁻² = 9[2 marks] - 2
Question 2. Prove that 5(n + 3)² - 5(n + 1)² is a multiple of 20 for all integer values of n.
Proof with Multiples▶ Show worked answerHide worked answer
- M1: 5(n² + 6n + 9) - 5(n² + 2n + 1)
- M1: 20n + 40
- C1: 20n + 40 = 20(n + 2), which is a multiple of 20
Answer: 20(n + 2), a multiple of 20[3 marks] - 3
Question 3. A scientist catches 60 fish in a lake, puts a tag on each fish and returns them to the lake.
A week later she catches 40 fish from the same lake. 8 of these 40 fish have a tag.
Work out an estimate for the number of fish in the lake.Capture-Recapture▶ Show worked answerHide worked answer
- M1: 60 ÷ N = 8 ÷ 40
- M1: 60 × 40 ÷ 8
- A1: 300
Answer: 300[3 marks] - 4
Question 4. Here is triangle XYZ.
Sam wants to work out the length x.
Should Sam use the sine rule or the cosine rule?
Give a reason for your answer.Combining the Sine Rule with Other Rules▶ Show worked answerHide worked answer
- B1: the cosine rule
- B1: two sides and the angle between them are given, and the side opposite that angle is unknown
Answer: The cosine rule, because two sides and the angle between them are given[2 marks] - 5
Question 5. f(x) = 2x + 1
g(x) = x - 9
fg(a) = 15
Work out the value of aComposite Functions▶ Show worked answerHide worked answer
- M1: 2(a - 9) + 1 = 15
- M1: a - 9 = 7
- A1: a = 16
Answer: 16[3 marks]