a: =30405-2340=28065
b: =12340+3405=15745
c: =15632+64168=79800
30405 - 11700 : 5 = 28065.
12340 + 20430 : 6 = 15745.
15632 + 16042 x 4 = 79800.
30405-2340=28095
12340+3405=15745
5632+64168=79800
\(\text{30405 - 11700 : 5 = 28065}\)
\(\text{12340 + 20430 : 6 = 15745}\)
\(\text{15632 + 16042 x 4 = 79800}\)