CAT 2022Slot 1QAQuestion & Solution

ArithmeticEasy

Question

A mixture contains lemon juice and sugar syrup in equal proportion. If a new mixture is created by adding this mixture and sugar syrup in the ratio 1 : 3, then the ratio of lemon juice and sugar syrup in the new mixture is

Options

1 : 4

1 : 5

1 : 6

1 : 7

Solution

1. Concept Used

  • Topic: Mixtures and Alligations — Successive Mixing
  • Formula: $$\text{Component in new mixture} = \frac{\text{(Parts of solution A)} \times \text{(Fraction of component in A)} + \text{(Parts of solution B)} \times \text{(Fraction of component in B)}}{\text{Total Parts}}$$

2. Calculation

The original mixture contains lemon juice and sugar syrup in equal proportion, i.e., 1 : 1. This means lemon juice constitutes (\frac{1}{2}) of the mixture and sugar syrup constitutes (\frac{1}{2}) of the mixture.

Pure sugar syrup contains 100% sugar syrup and 0% lemon juice.

The new mixture is formed by combining the original mixture and pure sugar syrup in the ratio 1 : 3. So assume we take 1 part of the original mixture and 3 parts of pure sugar syrup, giving a total of 4 parts.

Lemon juice in the new mixture:

$$\text{Lemon juice} = 1 \times \frac{1}{2} + 3 \times 0 = \frac{1}{2}$$

Sugar syrup in the new mixture:

$$\text{Sugar syrup} = 1 \times \frac{1}{2} + 3 \times 1 = \frac{1}{2} + 3 = \frac{7}{2}$$

Ratio of lemon juice to sugar syrup:

$$\text{Ratio} = \frac{1}{2} : \frac{7}{2} = 1 : 7$$


3. Solution

Answer = Option D

The ratio of lemon juice to sugar syrup in the new mixture is 1 : 7.