DSSSB 6 September 2024
Non Nursing Subjects
Hard

In what ratio should sugar costing ₹52.5 per kg be mixed with sugar costing ₹17 per kg so that there is a profit of 12% on selling the mixture at ₹44.8 per kg?

Appeared in: DSSSB 6 September 2024

Explanation

  • First, calculate the cost price (CP) of the mixture using the selling price (SP) and profit percentage. The formula is CP = SP / (1 + Profit%/100).
  • Given SP = ₹44.8 and Profit = 12%, the CP = 44.8 / 1.12 = ₹40 per kg.
  • Next, apply the rule of alligation. This rule helps find the ratio of two ingredients when their individual costs and the mean cost of the mixture are known.
  • The ratio of the dearer sugar (costing ₹52.5) to the cheaper sugar (costing ₹17) is calculated as (Mean Price - Cheaper Price) : (Dearer Price - Mean Price).
  • Substituting the values: (40 - 17) : (52.5 - 40) = 23 : 12.5.
  • To convert this to a whole number ratio, multiply both sides by 2, which gives 46 : 25.

Why Other Options Were Wrong

  • Option B: This ratio is incorrect. It may result from a miscalculation in the alligation step or an error in calculating the cost price of the mixture.
  • Option C: This ratio is incorrect. It likely arises from calculation errors, such as incorrectly subtracting the values in the alligation formula.
  • Option D: This ratio is incorrect. Such a result could occur if the selling price was mistakenly used as the mean price in the alligation rule, or from other arithmetic mistakes.

Related Visual

Visual explanation — Related Visual
Clinical Relevance
  • Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Mixtures and Alligation with Profit Percentage as background academic context rather than a clinical decision trigger.
  • This question tests quantitative aptitude, a skill essential for various competitive examinations, including those for nursing positions.
  • The ability to solve problems involving percentages, ratios, and mixtures is a measure of logical reasoning and analytical skills.
  • What if the mixture was sold at a loss of 10% instead of a profit? The cost price would be calculated as CP = 44.8 / (1 - 0.10) = 44.8 / 0.90 ≈ ₹49.78. This new CP would then be used in the alligation formula, leading to a different ratio.
How to Approach the Question
  • First, identify all the given values: the cost of the two types of sugar, the selling price of the mixture, and the profit percentage.
  • Recognize that the 'mean price' required for the alligation rule is the cost price (CP) of the mixture, not the selling price (SP).
  • Calculate the CP of the mixture by removing the profit from the SP using the formula: CP = SP / (1 + Profit%/100).
  • Set up the alligation diagram with the cost of the dearer item on one side, the cheaper item on the other, and the calculated mean price (CP) in the middle.
  • Perform the cross-subtraction: subtract the cheaper cost from the mean price, and subtract the mean price from the dearer cost.
  • The two results from the subtraction give the required ratio. Simplify the ratio to its simplest whole number form if necessary.
Concept Tested & Keywords
  • Concept Tested: Mixtures and Alligation with Profit Percentage
  • Stem keywords: ratio, sugar, costing, mixed, profit, selling mixture
  • Lead-in keywords: In what ratio

Question ID

QPLxlAoSRXqgPfQX1thnmL

Practise the full DSSSB 6 September 2024

Attempt every question from this paper in a timed mock, then review the full solution for each one.

More Mathematics Questions

More DSSSB 6 September 2024 Questions