In a group of three numbers first is double of second
and half of third. The average of three numbers is 42. Find the difference between the first number and third number?
A34Correct AnswerIncorrect Answer
B36Correct AnswerIncorrect Answer
C26 Correct AnswerIncorrect Answer
D28Correct AnswerIncorrect Answer
Solution
Let the first number be ‘x’ Second number = x/2 Third number = 2x According to the question, (x+x/2+2x)/3 = 42 (2x+x+4x)/6 = 42 7x = 42 × 6 x = 36 ∴ Required difference = 72 - 36 = 36
