There are three numbers, these are co-prime to each other are such that the…
2025
There are three numbers, these are co-prime to each other are such that the product of the first two is 551 and that of the last two is 1073. What will be the sum of three numbers :
- A.
67
- B.
129
- C.
85
- D.
19
Attempted by 48 students.
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Correct answer: C
Key idea: the common factor of the two given products is the middle number because the three numbers are pairwise coprime.
Factor the products: 551 = 19 × 29 and 1073 = 29 × 37.
The common factor between 551 and 1073 is 29, so the middle number is 29.
Find the other numbers: first = 551 ÷ 29 = 19, last = 1073 ÷ 29 = 37.
Sum = 19 + 29 + 37 = 85. Answer: 85