Shortcuts Method for Finding Cube Root

Number
cube
Last digit of cube
1
1^{3}=1\times 1\times 1 = 1
1
2
2^{3}=2\times 2\times 2 = 8
8
3
3^{3}=3\times 3\times 3 = 27
7
4
4^{3}=4\times 4\times 4 = 64
4
5
5^{3}=5\times 5\times 5 = 125
5
6
6^{3}=6\times 6\times 6 = 216
6
7
7^{3}=7\times 7\times 7=343
3
8
8^{3}=8\times 8\times 8 =512
2
9
9^{3}=9\times 9\times 9 = 729
9
10
10^{3}=10\times 10\times 10 = 1000
0

Find the cube root of the following Number

Questions 1) \sqrt[3]{3375}

Solution:

Step 1: Fist we need to ignore last three digit . i.e 375

Step 2: Now from the above table, find cube of a number which is less than and nearest to 3 .That number is 1 so left part of answer is 1

Step 3: Since the last digit of '3375' is 5 .From the above table the last digit of 5 comes from the cube of 5 . It means right part of answer will 5.

Answer = 15


Questions 2) \sqrt[3]{79507} = ?

Solution:

Step 1: Fist we need to ignore last three digit . i.e 507

Step 2: Now from the above table, find cube of a number which is less than and nearest to 79 .That number is 4 so left part of answer is 4

Step 3: Since the last digit of '79507' is 7 .From the above table the last digit of 8 comes from the cube of 3 . It mean right part of answer will be 3

Answer = 43


Questions 3) \sqrt[3]{373248} = ?

Solution:

Step 1: Fist we need to ignore last three digit . i.e 248

Step 2: Now from the above table, find cube of a number which is less than and nearest to 373 .That number is 7 so left part of answer is 7

Step 3: Since the last digit of '373248' is 8 .From the above table the last digit of 8 comes from the cube of 2 . It mean right part of answer will be 2

Answer = 72


Questions 4) \sqrt[3]{438976} = ?

Solution:

Step 1: Fist we need to ignore last three digit . i.e 976

Step 2: Now from the above table, find cube of a number which is less than and nearest to 438 .That number is 7 so left part of answer is 7

Step 3: Since the last digit of '438976' is 6 .From the above table the last digit of 6 comes from the cube of 6 . It mean right part of answer will be 6

Answer = 76


Questions 5) \sqrt[3]{238328} = ?

Solution:

Step 1: Fist we need to ignore last three digit . i.e 832328

Step 2: Now from the above table, find cube of a number which is less than and nearest to 238 .That number is 6 so left part of answer is 6

Step 3: Since the last digit of '238328' is 8 .From the above table the last digit of 8 comes from the cube of 2 . It mean right part of answer will be 2

Answer = 62

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