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all numbers greater than 1000 formed by using the digits 1, 3, 5, 7, no digit repeated in any number is A. 106656 B. 101276 C. 82171 D. 81273

Manvendra Singh chahar , 11 Years ago
Grade Upto college level
anser 1 Answers
Latika Leekha

Last Activity: 11 Years ago

as per the options, the question should have been the sum of numbers greater than 1000 formed by the digits 1, 3, 5 and 7 when no repetition is allowed.
The numbers formed using teh digits 1, 3, 5 and 7 will be
1357
1375
1573
1537
….…
In total, there would be 4! = 24 numbers to add.
Each vertical column would have an equal numbver of 1’s, 3’s, 5’s and 7’s.
Hence, since 24/4 = 6, the sum of each column would be 6 * (1+3+5+7) = 96.
Hence, the required sum is
96*1000 + 96*100 + 96*10 + 96*1
= 106656.
Hence, the correct option is (A).
Thanks & Regards
Latika Leekha
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