How do I find 2/3 of a whole number?

2 Answers
Feb 11, 2017

To find 2/3 of a whole number, you need to multiply the number by the numerator 2 and divide that product by the denominator 3.

Explanation:

If you represent any whole number by n;

then 2/3 of that number is 2/3 n, or (2n)/3

Looking at the last form you can see that you are multiplying the number n by 2 and dividing the product by 3.

Example if: n = 666

2/3 xx n = 2/3 xx(6666) = 13332/3 = 4444

Similarly if: n = 1

2/3 xx (1) = 2/3

Feb 11, 2017

Divide the number by 3 to find 'one-third,, then multiply by 2 to find 'two-thirds'.
2/3 of a number = n div 3 xx2

Explanation:

It is important to understand what two-thirds actually means...

Working with 'thirds' means you have started with a number or a quantity of something (like sweets) and divided it into THREE EQUAL parts, each part being 'one third' of the original amount.

1/3 of 12 means 12 div 3 = 4" "rarr 4 + 4+ 4 = 12

1/3 of 30 means 30 div 3 = 10" "rarr 10+10+10=30

1/3 of 15 means 15 div 3 = 5" "rarr 5+5+5=15

Now, to find 'two-thirds", simply means use 2 of the parts.

(SO, divide by 3 and then multiply by 2)

2/3 of 12 means: 12 div 3 xx 2 = 4xx 2 = 8

2/3 of 30 means:30 div 3 xx 2= 10xx2 = 20

2/3 of 15 means: 15 div 3 xx2= 5xx2

So for a number, let's call it n, can write this as:

2/3 xx n, " or " (2xxn)/3" or "ndiv3xx2" or "nxx2div3

It does not matter whether you multiply or divide first.

Dividing first makes the numbers smaller and easier to work with.

Finding 2/3 of 63. Compare the numbers:

63 div 3 xx 2 = 21 xx 2 = 42

and

63 xx2 div 3 = 126 div 3 = 42