A bag has Rs. 43 in the form of 5 rupee, 50 paise and 10 paise coins in the ratio of 1 : 5 : 11. What is the total number of 50 paise coins?

\[\begin{array}{*{20}{c}} {{\text{Rs}}{\text{. 5}}}&{}&{50{\text{ Paise}}}&{}&{{\text{10 Paise}}}&{} \\ 1&:&5&:&{11}&{ \to {\text{Number of coins}}} \end{array}\]
(5 + 2.5 + 1.10) units = 43
8.60 units = 43
1 unit \[ = \frac{{43 \times 100}}{{860}} = 5\]
Number of 50 paise coins = 5 × 5 = 25