Worksheet: Cube - 2 | Mental Mathematics for Class 8 PDF Download

Q1: Find the cube roots by prime factorization method
(i) 15625
(ii) 2744
(iii) 125/2197
(iv) 5832
(v) 64000
(vi) 10648
(vii) 1331
(viii) 1728

Q2: Is 256 a perfect cube? If not, find the smallest number by which it should be divided to get a perfect cube.

Q3: Three numbers are in the ratio 1:2:3 and the sum of their cubes is 4500. Find the numbers.

Q4: Find the cubes of these numbers.
(i) .4
(ii) 8
(iii) 15
(iv) .02
(v) 1.1
(vi) .011

Q5: if 6ⁿ⁺² = 1296 , then

Q6: (i)The least number by which 72 be multiplied to make it a perfect cube is _____________
(ii) If 8x³ = 216, then x ix ____
(iii) The cube of .5 is _____
(iv) There are _________ perfect cubes between 1 and 1000.
(v) The digit at the ones place of 23³ is ____
(vi) The cube of the even natural number is ____

Q7: (i) 648 is not perfect cube?
(ii) 999 is a perfect cube
(iii) Square of a number is positive, so the cube of that number will also be positive
(iv) 125 × 8 × 27 is a perfect cube
(v) For an integer p, p³ is always greater than p²
(vi) .8³ = 5.12

Q8: Cube root of the expression 125²
(a) 5
(b) 25
(c) 10
(d) 125

Q9: Which of these is a perfect cube
(a) 216
(b) 392
(b) 8640
(d) 243

Q10: Which of these is not a perfect cube
(a) 729
(b) 2197
(c) -1331
(d) 169