Question 7
Number BasesIf 31410 − 2567 = 340x, find x
- A.7
- B.8
- C.9
- D.10
Show the answer and explanation
Answer: A (7)
Explanation
2567 = 2×49 + 5×7 + 6 = 139, so the left side is 314 − 139 = 175. Then 3x2 + 4x = 175, i.e. (x − 7)(3x + 25) = 0, so x = 7.