240 : (х + 3) - 5 = 7
240 : (х + 3) = 7 + 5
240 : (х + 3) = 12
х + 3 = 240 : 12
х + 3 = 20
х = 20 - 3
х = 17
----------------------------------------------------------
240 : (17 + 3) - 5 = 7
240 : (17 + 3) = 7 + 5
240 : 20 = 12
12 = 12
16 * (11 - х : 8) = 64
11 - х : 8 = 64 : 16
11 - х : 8 = 4
х : 8 = 11 - 4
х : 8 = 7
х = 7 * 8
х = 56
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16 * (11 - 56 : 8) = 64
16 * (11 - 7) = 64
16 * 4 = 64
64 = 64