The sum of a number's square, its cube, and its next number's cube is 205. What is the number?
Show answer & explanation
Correct answer: B
Explanation
The correct answer is option 2 i.e. 4.
Let the number be a.
According to the question;
a2 + a3 + (a +1)2 = 205
Try the hit and trial method.
Option 1: 3
32 + 33 + (3 +1)3 = 9 + 27 + 64 = 100
Option 2: 4
42 + 43 + (4 +1)2 = 16 + 64 + 125 = 205
Hence, option 2 is the correct answer.