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प्रश्न
A positive number is 5 times another number. If 21 is added to both the numbers, then one of the new numbers becomes twice the other new number. What are the numbers?
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उत्तर
Let the numbers be x and 5x. According to the question,
21 + 5x = 2(x + 21)
21 + 5x = 2x + 42
Transposing 2x to L.H.S and 21 to R.H.S, we obtain
5x − 2x = 42 − 21
3x = 21
Dividing both sides by 3, we obtain
x = 7
5x = 5 × 7 = 35
Hence, the numbers are 7 and 35 respectively.
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