The 1st problem: 2 2/5 + 1/15

How your friend did the work:
2 2/5 + 1/15
2 12/15 + 1/15
2 13/15***I think it's 2 7/15 am I right?

The 2nd problem: 9 1/2 - 5 7/12
How your friend did the work:
9 1/2 - 5 7/12
9 6/12 - 5 7/12
8 18/12 - 5 7/12
3 11/12***I got the same thing am I right?

The 3rd problem: -4 7/8 x 2/3
How your friend did the problem:
-4 7/8 x 2/3
-4 14/24
-4 7/12***I got -3 1/4 am I right?

The 4th problem: -3 1/5 ÷ -2/3
-3 1/5 ÷ -2/3
-16/5 x -3/2
-8/5 x -3/1
-24/5
-4 4/5***I got the same thing am I right?

Thank you for the help!!

1 answer

You're ok until the last one
-8/5 x -3/1 = +24/5
You lost the minus sign.