Question
A two-digit natural number has the property that the
digit in the tens place is the square of the digit in the units place. When the original number is added to the number formed by reversing its digits, the total is 132. Determine 65% of the difference between the original number and the reversed number.Solution
Let the unit digit of original number be 'a'. So, tens digit of original number = a2 ATQ, 10a2Â + a + 10a + a2Â = 132 Or, 11(a2Â + a) = 132 Or, a2Â + a - 12 = 0 Or, a2Â + 4a - 3a - 12 = 0 Or, a(a + 4) - 3(a + 4) = 0 Or, (a - 3) (a + 4) = 0 So, 'a' = 3 or 'a' = - 4 Since, the original number is natural. So, 'a' = 3 Therefore, required value = 0.65 X (10a2Â + a - 10a - a2) = 0.65 X 9 X (32Â - 3) = 0.65 X 54 = 35.1
25, 32, 47, 77, 126, 198
- Find the wrong number in the given number series.
350, 289, 238, 197, 158, 145 15, 34, 13, 32, 11, 28
Find the wrong number in the given number series.
24, 120, 721, 5040, 40320, 362880
72, 80, 89, 153, 180, 394Â
360, 322, 286, 248, 220, 190
3Â Â Â Â Â 5Â Â Â Â Â Â 9Â Â Â Â Â 17 Â Â Â Â Â Â 32 Â Â Â Â Â Â Â 65
...Find the wrong number in the given number series.
65, 91, 127, 163, 217, 271
1, 1, 3, 15, 105, 942
120, 139, 196, 291, 420, 595