Question
In a two digit positive number, the digit in the
unit’s place is equal to the square of the digit in ten’s place, and the difference between the number and the number obtained by interchanging the digits is 54. What is 60% of the original number?Solution
Let the number = 10x + x 2 According to the question, 10x + x2 - (10x2 - x) = 54 9(x2 - x) = 54 x 2 - x = 6 x2 - x – 6 = 0 ( x - 3) (x + 2) = 0 x = 3 or x = -2 Number = 39 [x ≠ 2] => 60% of 39 = (60/100) × 39 = 23.4
Mirror formula is
In a nuclear reaction, the product nucleus has higher binding energy per nucleon than the reactants. Which of the following is correct?
Where is the magnetic force of a bar magnet the strongest?
Which metal is liquid at room temperature? Â
If a body of mass 5 kg is raised to 10 meters height, find its potential energy. (g = 9.8 m/s²) Â
What does the slope of a velocity-time graph represent?
The current across the 3 ohm resistance in the given circuit is:
In an electric motor, energy is transformed from:
What is the work done when a force of 10 N moves an object by 5 m in the direction of the force? Â
Global warming is expected to result in
Relevant for Exams:
