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प्रश्न
Rehana went to a bank to withdraw ₹ 2000. She asked the cashier to give her ₹ 50 and ₹ 100 notes only. Rehana got 25 notes in all. Find how many notes of ₹ 50 and ₹ 100 did she received.
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उत्तर
Let the number of ₹ 50 notes and ₹ 100 notes be x and y respectively
According to the given information,
x + y = 25 ...(1)
50x + 100y = 2000 ...(2)
Multiply equation (1) by 50 we obtain
50x + 50y = 1250 ...(3)
Subtracting equation (3) from equation (2), we obtain
50y = 750
y = 15
Substituting in equation (1), we have x = 10
Hence, Rehana has 10 notes of ₹ 50 and 15 notes of ₹ 100.
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