The average of three numbers is 77.The first number is twice the second and…
2024
The average of three numbers is 77.The first number is twice the second and the second number is twice the third. Find the first number?
- A.
77
- B.
120
- C.
100
- D.
132
Attempted by 94 students.
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Correct answer: D
Let the third number be x. Then the second is 2x and the first is 4x.
Sum of the three numbers = 4x + 2x + x = 7x.
Average = (7x)/3. Set this equal to 77: (7x)/3 = 77 ⇒ 7x = 231 ⇒ x = 33.
First number = 4x = 4 × 33 = 132.
Answer: 132