1) х-350=240
х=240+350
х=590
2) 291+а=652
а=652-291
а=361
3) х:30=9
х=9*30
х=270
4) 70*х=490
х=490:70
х=7
5 2/3 - 4 1/3 = 1 1/3
12 1/3 - 9 1 /4 = 12 4/12 - 9 3/12 = 3 1/12
5 2/3 - 1/6 = 5 4/6 - 1/6 = 5 3/6 = 5 1/3
10 8/9 - 2/3 = 10 8/9 - 6/9 = 10 2/9
6 3/4 - 2 1/2 = 6 3/4 - 2 2/4 = 4 1/4
4 2/5 - 1 1/10 = 4 4/10 - 1 1/10 = 3 3/10