Question 10 of 29intermediate🔧 ApplyNumerical4 marks
You are told that 1331 is a perfect cube. Can you guess without factorisation what its cube root is? Similarly, guess the cube roots of 4913, 12167, and 32768.
(i)
∛1331
Answer
11
(ii)
∛4913
Answer
17
(iii)
∛12167
Answer
23
(iv)
∛32768
Answer
32
Explanation
(i) 1331 ends with 1, so cube root ends with 1. 11³ = 1331 (ii) 4913 ends with 3, so cube root ends with 7. 17³ = 4913 (iii) 12167 ends with 7, so cube root ends with 3. 23³ = 12167 (iv) 32768 ends with 8, so cube root ends with 2. 32³ = 32768