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Question
A postman can sort out 738 letters in 6 hours. How many letters can be sorted in 9 hours?
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Solution
Let the required number of letters be x.
| Number of letters | 738 | x |
| Required time to sort in hours | 6 | 9 |
They are in direct proportion.
`(x_1)/(y_1) = (x_2)/(y_2)`
`738/6 = x/9`
x = `(739 xx 9)/6`
x = 1107
In 9 hours 1107 letters can be sorted.
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