Hence, the numbers are 8, 16 and 24.
= 3x8 = 24
EXERCISE 12.2
1. Find the cube root of the following numbers by prime factorisation.
(ii) 1000
(iii) 1728
(vi) 68921
(vii) 343000
(ix) 91125
(x) 35937
(i) 125
(v) 15625
Answers
Answer:
Step-by-step explanation:
i)125
125 (divide by 5)
25 (divide by 5)
5 (divide by 5)
1
125=5×5×5
5³=125
ii)1000
1000 (divide by 5)
200 (divide by 5)
40 (divide by 5)
8 (divide by 2)
4 (divide by 2)
2 (divide by 2)
1
1000=5×2×5×2×5×2=10×10×10
10³=1000
(iii)1728
1728 (divide by 2)
864 (divide by 2)
432 (divide by 2)
216 (divide by 2)
108 (divide by 2)
54 (divide by 2)
27 (divide by 3)
9 (divide by 3)
3 (divide by 3)
1
1728=2×2×2×2×2×2×3×3×3=8×8×8
8³=1728
vi)68921
68921 (divide by 41)
1681 (divide by 41)
41 (divide by 41)
1
68921=41×41×41
41³=68921
v)15625
15625 (divide by 5)
3125 (divide by 5)
625 (divide by 5)
125 (divide by 5)
25 (divide by 5)
5 (divide by 5)
1
15625=5×5×5×5×5×5=25×25×25
25³=15625
vi)343000
343000 (divide by 7)
49000 (divide by 7)
7000 (divide by 7)
1000 (divide by 5)
200 (divide by 5)
40 (divide by 5)
8 (divide by 2)
4 (divide by 2)
2 (divide by 2)
1
343000=7×7×7×5×5×5×2×2×2=70×70×70
70³=343000
vii)91125
91125 (divide by 5)
18225 (divide by 5)
3645 (divide by 5)
729 (divide by 3)
243 (divide by 3)
81 (divide by 3)
27 (divide by 3)
9 (divide by 3)
3 (divide by 3)
1
91125=5×5×5×3×3×3×3×3×3=45×45×45
45³=91125
viii)35937
35937 (divide by 3)
11979 (divide by 3)
3993 (divide by 3)
1331 (divide by 11)
121 (divide by 11)
11 (divide by 11)
1
35937=3×3×3×11×11×11=33×33×33
33³=35937