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

2 Answers
Feb 11, 2017

Answer:

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

Answer:

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#