Same chapter4 marksDifficulty: Hard
A two-digit number is such that the sum of its digits is 9, and reversing the digits increases the number by 27. Find the number.
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4 marksDifficulty: Hard
A boat covers 24 km downstream in 2 hours and returns upstream in 3 hours. Find the speed of the boat in still water and the speed of the current.
Original Khojo Papers practice question — not from a past board paper.
Answer
The boat travels at 10 km h−1 and the current flows at 2 km h−1.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Downstream speed is 12 km h−1 and upstream 8 km h−1. Adding and halving gives the speed in still water, and subtracting and halving gives the speed of the current.
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