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प्रश्न
How many different numbers, greater than 50000 can be formed with the digits 0, 1, 1, 5, 9.
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उत्तर
Numbers greater than 50000 can either have 5 or 9 in the first place and will consist of 5 digits.
Number of arrangements having 5 as the first digit =\[\frac{4!}{2!}\]
Number of arrangement having 9 as the first digit =\[\frac{4!}{2!}\]
∴ Required arrangements =\[\frac{4!}{2!}\]+\[\frac{4!}{2!}\]=24
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