1)
к*7=80-31
к*49
к=7
2)27:<span>b=53-44
27=</span><span>b*9
</span><span>b=3</span>
3*200=600
2*240=480
480+600=1080
1080+120=<u>1200</u>
А) 508, 580, 805, 850
b) 500, 505, 508, 550, 555, 558, 585, 800, 805, 808, 850, 855, 858, 885, 888
12:35,.....................