integers

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integers

by ritula » Fri Sep 19, 2008 2:36 am
How many integers between 324,700 and 458,600 have tens digit 2 and units digit 1?

1,339
1,352
1,353
10,030
10,300
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by Indradeep » Fri Sep 19, 2008 4:43 am
What is the OA?
Sure answer is within the options?

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by AKS-AKS » Fri Sep 19, 2008 4:46 am
Its simple..

You are required to get 2 in tens place and 1 in units place.

So from any interval of 100 digits we have just one value satisfying the condition ie..21

Ans: Substract the initial value from final value and divide it by 100.

458,600 - 324,700 = 133900
divide it by 100 because for each 100 interval we have one value satisfying the condition

133900/100 = 1339

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by Indradeep » Fri Sep 19, 2008 4:57 am
Yeah I get it.
The lowest number would be 324721 and the highest number is 458521
Thus the difference is 133800
and we need to divide by 100
Thus number would be 1338.
But because the boundary numbers are also considered, we need to add 1.
Thus 1339 is the answer.
I forgot to add the 1.

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OA

by ritula » Fri Sep 19, 2008 5:57 am
Yes OA is A indeed
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