10 questions · Form 4 Additional Mathematics Bab 10: Index Numbers
10 questions · plays in fullscreen
Prefer reading to quizzing? All 10 questions are listed below with the answer and explanation under each one.
1. The price index of sugar in 2022 based on 2018 is 112. The price index of sugar in 2024 based on 2022 is 125. Find the price index of sugar in 2024 based on 2018.
Answer: A
I₂₀₂₄/₂₀₁₈ = (I₂₀₂₂/₂₀₁₈ × I₂₀₂₄/₂₀₂₂) / 100 = 112 × 125100 = 14000100 = 140.
2. The price index of a tool in 2023 based on 2021 is 90. If the tool cost RM 150 in 2021, how much did it cost in 2023?
Answer: A
Q₂₀₂₃ = 90 × 150100 = 13500100 = RM 135.
3. Three items have price indices of 110, 125, and x with weightages of 3, 2, and 5 respectively. If the composite index is 120, find the value of x.
Answer: A
Ī = 110(3) + 125(2) + 5x3 + 2 + 5 => 120 = 330 + 250 + 5x10 => 1200 = 580 + 5x => 5x = 620 => x = 124.
4. The price index of a textbook in 2024 based on 2020 is 115. If the textbook costs RM 46 in 2024, find its price in 2020.
Answer: A
115 = (46Q₂₀₂₀) × 100 => Q₂₀₂₀ = 46 × 100115 = 4600115 = RM 40.
5. A price index of 85 indicates that the price of an item has:
Answer: A
Since 85 is less than 100, the price decreased by (100 - 85)% = 15% compared to the base year.
6. If the price index of a good in 2024 based on 2020 is 140, what is the percentage increase in price from 2020 to 2024?
Answer: A
Percentage increase = I - 100 = 140 - 100 = 40%.
7. If all components in a composite index increase by 10%, what happens to the composite index?
Answer: A
If every component index I_i becomes 1.10 × I_i, the composite index becomes Σ(1.10 I_i w_i) / Σw_i = 1.10 × Ī, which represents a 10% increase.
8. The price index of a shirt in 2022 based on 2020 is 125, and the price index in 2024 based on 2022 is 110. Calculate the price index in 2024 based on 2020.
Answer: A
I₂₀₂₄/₂₀₂₀ = (I₂₀₂₂/₂₀₂₀ × I₂₀₂₄/₂₀₂₂) / 100 = 125 × 110100 = 13750100 = 137.5.
9. In a pie chart representing weightages, component X occupies an angle of 90°. What is the weightage of component X as a fraction of the total?
Answer: A
Weightage fraction = 90° / 360° = 14.
10. The prices of a commodity in 2019 and 2023 are RM 15.00 and RM 18.75 respectively. Calculate the price index in 2023 based on 2019.
Answer: A
I = (18.7515.00) × 100 = 1.25 × 100 = 125.