N is a 3-digit number. The middle digit of N is equal to the sum of the other two digits and the sum of the digits is 10. How many such numbers (N) can be possible?
5
Let the digits of N be \(a,b,c\) (hundreds, tens, units) with \(b=a+c\) and \(a+b+c=10\). Substituting \(b=a+c\) gives \(2b=10 \Rightarrow b=5\), so \(a+c=5\) with \(a\geq1\) (leading digit). The valid pairs are \((a,c)=(1,4),(2,3),(3,2),(4,1),(5,0)\), giving the numbers 154, 253, 352, 451, 550 — 5 numbers in total.
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Important Questions from Number System
What is the value of 1 2 + 2 2 + 3 2 + ......21 2 ?
Which sequence is correct to represent the hierarchical chain of number system?
(Where N - Natural Numbers
W - Whole Numbers
Q - Rational Numbers
Z - Integers)
What must be added to 45680 to make it exactly divisible by 9?
How many zeroes are there at the end of the following product?
1 x 5 x 10 x 15 x 20 x 25 x 30 x 35 x 40 x 45 x 50 x 55 x 60
Let XYZ be a three-digit number, where (x + y + Z) is not a multiple of 3. Then (XYZ + YZX + ZXY) is not divisible by
