How to quickly find cube root?
Tell your friend to take any 2 digit number and calculate its cube. Tell him to tell you the answer I.e. give you the perfect cube number.
Step 1:Note the last (unit place) digit. If it is 0,1,4,5,6 or 9 the unit place digit of cube root is the last digit itself. If it is 2,3,7 or 8 the last digit of the cube root is 8,7,3 or 2 respectively.
Step 2:Leave aside the last 3 digits of the perfect cube from right.
Step 3: Consider the remaining number. This number will be maximum a 3 digit number. (Learn by heart cubes of 0 to 9). Find the largest perfect cube smaller than this considered number.
Step 4: The cube root of this largest perfect cube is the tens place digit of the cube root of the number given by your friend.
Step 5: write step 4's answer. To its right write answer of steps 1.
Step 6: This is the answer. I.e. the 2 digit number originally taken by your friend. I mean the cube root of the number told (given) by your friend.
Tell your friend to take any 2 digit number and calculate its cube. Tell him to tell you the answer I.e. give you the perfect cube number.
Step 1:Note the last (unit place) digit. If it is 0,1,4,5,6 or 9 the unit place digit of cube root is the last digit itself. If it is 2,3,7 or 8 the last digit of the cube root is 8,7,3 or 2 respectively.
Step 2:Leave aside the last 3 digits of the perfect cube from right.
Step 3: Consider the remaining number. This number will be maximum a 3 digit number. (Learn by heart cubes of 0 to 9). Find the largest perfect cube smaller than this considered number.
Step 4: The cube root of this largest perfect cube is the tens place digit of the cube root of the number given by your friend.
Step 5: write step 4's answer. To its right write answer of steps 1.
Step 6: This is the answer. I.e. the 2 digit number originally taken by your friend. I mean the cube root of the number told (given) by your friend.
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