I'm in class 5.5. I haven't learned the addition and subtraction of different denominators 1. Xiao Gang wanted to read a story book. He read 1 / 12 of the whole book on the first day, and 1 / 24 of the whole book more on the second day than on the first day. How many parts of the book are not read now? 2. Take off type (1)3\8+5\6-7\12 (2)9\20+4\15+1\6 (3)3\5+7\10-8\15 (4)3\7-8\21+9\14 3. Simple (1)3\4+9\20+6\20 (2)2\5-1\2+3\5 (3)5\12-(5\12-2\5) (4)23\39+5\13+8\13 Come on, 555 555

I'm in class 5.5. I haven't learned the addition and subtraction of different denominators 1. Xiao Gang wanted to read a story book. He read 1 / 12 of the whole book on the first day, and 1 / 24 of the whole book more on the second day than on the first day. How many parts of the book are not read now? 2. Take off type (1)3\8+5\6-7\12 (2)9\20+4\15+1\6 (3)3\5+7\10-8\15 (4)3\7-8\21+9\14 3. Simple (1)3\4+9\20+6\20 (2)2\5-1\2+3\5 (3)5\12-(5\12-2\5) (4)23\39+5\13+8\13 Come on, 555 555

1. On the first day, I read 1 / 12 = 2 / 24 of the whole book
The next day I read more than the first day
The next day I read 2 / 24 + 1 / 24 = 3 / 24
There are still a few parts of the book that haven't been read
=1-(2/24+3/24)
=1-5/24
=19/24
2. Take off type
(1)3\8+5\6-7\12
=9/24+20/24-14/24
=29/24-14/24
=15/24
=5/8
(2)9\20+4\15+1\6
=54/120+32/120+20/120
=106/120
=53/60
(3)3\5+7\10-8\15
=18/30+21/30-16/30
=39/30-16/30
=23/30
(4)3\7-8\21+9\14
=18/42-16/42+27/42
=2/42+27/42
=29/42
3. Simple
(1)3\4+9\20+6\20
=3/4+15/20
=3/4+3/4
=6/4
=1.5
(2)2\5-1\2+3\5
=2/5+3/5-1/2
=1-1/2
=1/2
(3)5\12-(5\12-2\5)
=5/12-5/12+2/5
=0+2/5
=2/5
(4)23\39+5\13+8\13
=23/39+13/13
=1 and 23 / 39