Home › CBSE Class 8 › mathematics › cubesandcuberoots › Sum of the consecutive odd numbers needed to obt…
Sum of the consecutive odd numbers needed to obtain 5³ = 125 is:
A21 + 23 + 25 + 27 + 29
B11 + 13 + 15 + 17 + 19
C23 + 25 + 27
D31 + 33 + 35 + 37
Answer & Solution
Correct answer: A. 21 + 23 + 25 + 27 + 29
From the chapter's pattern: 1 = 1³; 3+5 = 2³; 7+9+11 = 3³; 13+15+17+19 = 4³; 21+23+25+27+29 = 5³ = 125. Each cube n³ is the sum of n consecutive odd numbers, picking up where the previous block ended.
Related questions
Find the smallest perfect cube that is divisible by both 8 and 27.The cube of which number among the following is a 7-digit number?Find ∛(0.064).Which of the following statements is TRUE?A child stacks unit cubes (side 1 cm) to make a larger cube of side 4 cm. The number of unIs 1188 a perfect cube? If not, the smallest natural number by which 1188 must be DIVIDED Compute ∛13824 by prime factorisation.Compute 25³ − 24³ using the pattern (n+1)³ − n³ = 1 + 3·n·(n+1):