Page 89 - Start Up Mathematics_8 (Non CCE)

(vi) The cube of a two digit number may have seven or more digits.
(vii) The cube of a single digit number may be a single digit number.
4. You are told that 1,331 is a perfect cube. Can you guess without factorisation what is its cube root?
Similarly, guess the cube roots of 4913, 12167, 32768.

Exemplar Problems

1. If m is the cube root of n, then n is:

(a) m 3 (b) m (c) n (d) 3 m
3
2. One digit in the cube of 38 is _______.
3. There is no cube root of a negative integer. (True/False)
4. 3 827+ = 3 8 + 3 27. (True/False)
5. Difference of two perfect cubes is 189. If the cube root of the smaller of the two numbers is 3, find the
cube root of the larger number.
6. Evaluate : 3 27 + 3 0 008 +. 3 0 064.

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