Subtraction with renaming

Question

Am very confused. Am trying to teach my little brother but am getting everything wrong. I have the right answer but the work does not add up to that.
6 - 3 2/5
I got 3 2/5 but the answer is 2 3/5 I don’t understand can you explain what I have to do so I can explain it to him in the most simpliest way.

5 1/4 - 2 3/4
I got 3 2/4 but the answer is 2 2/4 ?
I did 5-2 =3 then 3_1= 2/4

9 3/8 - 8 7/8
I got 1 4/8 but the answer is 4/8

12 3/10 - 7 7/10
I got 5 4/10 but the answer is 4 6/10
I don’t understand I also have the lesson that was given but I still don’t understand it

Answer 1

1. First subtract the integer portion. We have 6-3=3. Next, subtract the fraction. 3-2/5 = 2 3/5

2. Do the same thing. 5 - 2 = 3. 1/4 - 3/4 = -2/4. Now add the two. 3+-2/4=3-2/4=2 2/4 or 2 1/2

3. 9 - 8 = 1. 3/8 - 7/8 = -4/8. Now we add the two. 1+-4/8=1-4/8=4/8 or 1/2

4. 12 - 7 = 5. 3/10-7/10 = -4/10. Add the two: 5+-4/10=5-4/10=4 6/10 or 4 3/5

Answer 2

6 - 3 2/5

First, change 6 to 5 5/5. Do you see how they're the same?

https://www.mathsisfun.com/fractions_subtraction.html

5 5/5 - 3 2/5 = 2 3/5

Now try the other problems.

Answer 3

6 - 3 2/5

we need to borrow 5/5 from the 6 You can not subtract 2/5 from nothing in this grade

5 5//5 - 3 2/5

2 3/5
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I suppose in a higher grade you could say
6 - 3 2/5 = 3 -2/5
that is 2 3/5
but no one does it that waay