Question
The sum of the digits of a two-digit number is 11. When
the digits are reversed, the new number is 27 more than the original number. Find the original number.Solution
Let the original number be 10a + b, where a is tens digit and b is units digit. Given: a + b = 11 ...(1) Reversed number = 10b + a, and 10b + a = (10a + b) + 27 10b + a = 10a + b + 27 9b − 9a = 27 b − a = 3 ...(2) From (1) and (2): a + b = 11 b − a = 3 Add: 2b = 14 ⇒ b = 7 Then a = 11 − 7 = 4 Original number = 10a + b = 40 + 7 = 47
More No. System Questions
(11/12) × (18/22) × (4/3) + 3 = ?2
- What will come in the place of question mark (?) in the given expression?
32% of 74% of ? = 16% of 37% of 180 30% of 215 + 135% of ? = 469.5
800 + 900 X (3)-2 - ? = 25 X 60 ÷ 2
1555.5 + 1000.8 – 1354.3 = ? + 52
- What will come in place of (?), in the given expression.
(4² + 6²) × 2 = ? - 55% of 220 – 15% of 40 = 20% of ?
50 ÷ 2.5 × 64 + ? = 1520
(-251 × 21 × -12) ÷ ? = 158.13
Relevant for Exams:
