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प्रश्न
A group of 21 students paid ₹ 840 as the entry fee for a magic show. How many students entered the magic show if the total amount paid was ₹ 1680?
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उत्तर
Let the required number of students be x.
| Number of students | 21 | x |
| Entry fees in ₹ | 840 | 1680 |
As the number of students increases the entry fees also increases.
∴ They are in direct proportion.
∴ `(x_1)/(y_1) = (x_2)/(y_2)`
`21/840 = x/1680`
x = `(21 xx 1680)/840`
x = 42.
∴ The number of students entered magic show = 42
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