Test Index

Ratio and Proportion

Question : 85 of 112

Marks: +1, -0

₹ 43 .

Solution:

Concept:

Use the given ratio to represent the unknown counts of 1 and 2 rupee coins with a common variable.

Explanation:

Let the number of 1 rupee coins be

3k

and 2 rupee coins be

2k

(since ratio

3:2

Then number of 5 rupee coins

= 23 - (3k + 2k) = 23 - 5k

Total value equation:

1 \cdot 3k + 2 \cdot 2k + 5 \cdot (23 - 5k) = 43

Simplify:

3k + 4k + 115 - 25k = 43

Combine like terms:

(3k+4k-25k) + 115 = 43 \implies -18k + 115 = 43

Solve:

-18k = 43 - 115 \implies -18k = -72 \implies k = 4

Thus, number of 1 rupee coins

= 3k = 3 \times 4 = 12

Answer:

Go to Question:

Prev Question

Next Question