The key to answering this question is to find your "lowest common denominator." (The denominator is the number below the line of the fraction.)
If you multiply the denominators of the two fractions (4 and 5) you will come up with a common denominator (20). That will usually be your lowest common denominator.
Then multiply each numerator (the number above the line of the fraction) by the denominator of the other fraction.
The numerator of one-fourth is 1; the denominator of two-fifths is 5. Therefore, multiply 1 x 5 and you get 5.
The numerator of two-fifths is 2; the denominator of one-fourth is 4. Therefore, multiply 2 x 4 and you get 8.
Finally, add the results of your calculations: 5 + 8 = 13
Your new numerator is 13 and your new denominator is 20.
2 and 13/20
1
It's not ! One fourth (or 1/4) of ten is 2 and 1/2
They add to: 4 and 1/5
22 and 1/2
I think it's 1 and 2/5
2 and 6/5 or 3 and 1/5
too hard
3
2/5 + 1/5 = 3/5
It is: 1 and a 1/2 plus 3/5 = 2 and 1/10 or 2.1
4/5+ 2/5 = 6/5 = 1/1/5 or 1.2