
To add or subtract fractions, remember that you need a common denominator.
But I noticed that
4/6 = 2/3
so your question 2/3+4/6 becomes
2/3+2/3
= 4/3 (or 1 1/3 as some folks would insist)

When fractions are added, they need to have the same denominator. Then add the numerators.
4/6 = 2/3
2/3 + 2/3 = 4/3 = 1 1/3
Check this site for more information about fractions.
http://www.aaamath.com/fra.html

2/3 + 4/6
Find the LCD.
The LCD is 6 because it is the smallest number that both denominators given fit into without a remainder.
LCD = 6.
We now divide the LCD by each denominator and then multiply the quotient by each numerator.
6 divided by 3 = 2
2 x 2 = 4
The left side fraction is now 4/6.
=================================
6 divided by 6 = 1
4 x 1 = 4
The right side fraction remains 4/6.
We NOW have this:
4/6 + 4/6 =
Notice that we now have the SAME DENOMINATOR for each fraction. This is the number reason why we need to find the LCD.
We simply add the numerators and then reduce the fraction (if needed).
4/6 + 4/6 = 8/6
We can reduce 8/6 to 4/3.
Done!