What approximate value will come in place of question mark (?) in the…
2024
What approximate value will come in place of question mark (?) in the following questions (You are not expected to calculate the exact value).
- A.
59
- B.
53
- C.
65
- D.
50
- E.
43
Attempted by 7 students.
Show answer & explanation
Correct answer: A
Concept
In an approximation problem, replace each term by the nearest value that is easy to compute, then solve. Three standard rounding tools: a square root close to a perfect square equals that root; a fraction "of" a number is a multiplication; and a near-integer decimal rounds to the integer.
Application
Square root: √840.99 ≈ √841 = 29, because 292 = 841.
Fraction of a number: (14/19) of 361.09 ≈ (14/19) × 361. Since 361 ÷ 19 = 19, this is 14 × 19 = 266.
Add the two parts: 29 + 266 = 295.
Solve for the unknown: 295 = ? × 4.88, so ? = 295 ÷ 4.88 ≈ 60.46.
Cross-check
Among the offered values, 60.46 is nearest to 59 (59 × 4.88 = 287.9, only about 7 away from 295), while the next closest, 65, gives 65 × 4.88 = 317.2 — over 22 away. So 59 is the intended approximate answer.