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An n-digit number is a positive number with exactly n digits. Nine hundred distinct n-digit numbers are to be formed using only the three digits 2, 5 and 7. The smallest value of n for which this is possible, is

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Important Questions on X+2 Maths

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Let a1,a2,,a10 be in AP and h1,h2,,h10 be in HP. If a1=h1=2 and a10=h10=3, then a4h7 is
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If the integers m and n are chosen at random between 1 and 100, then the probability that a number of the form 7m+7n is divisible by 5 equals
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Let S1,S2,. be squares such that for each n1, the length of a side of Sn equals the length of a diagonal of Sn+1. If the length of a side of S1 is 10 cm, then for which of the following values of n is the area of Sn less than 1 sq. cm
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If a, b, c, d are positive real numbers such that a+b+c+d=2, then M=(a+b)(c+d) satisfies the relation
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How many different nine-digit numbers can be formed from the number 223355888 by rearranging its digits so that the odd digits occupy even positions?
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The area bounded by the curves y=|x|-1 and y=-|x|+1 is