3questions can you answer them? plz all of them: )

1. no, she is not correctbecause 1/2 of a small wall is not the same as 1/2 of a large wall. Lets say the small wall is 4 ftso Sandra painted 1/2*4 = 2 ft...now lets say the lg wall is 8 ft...so Kenneth painted 1/2*8 = 4 ft. 

2. 3 3/8 + 4 1/8
    3 + 4 = 7
    3/8 + 1/8 = 4/8
    7 + 4/8 = 7 4/8so ur answer is 7 4/8

3. 5/10 + 68/100 = 50/100 + 68/100 = 118/100
    8/10 + 4/100 = 80/100 + 4/100 = 84/100
    3/10 + 16/100 = 30/100 + 16/100 = 46/100