(4) 100+121+144=169+196
365=365
<span>3438+х:6=10004 </span>
<span>х:6=10004-3438 </span>
<span>х:6=6566</span>
<span>х=6566*6</span>
<span>х=39396</span>
<span>проверка:</span>
<span>3438+39396:6=10004</span>
<span>10004=10004</span>
<span>
</span>
<span><span>(800-180):х=20 </span></span>
<span><span>620:х=20</span></span>
<span><span>х=620:20</span></span>
<span><span>х=31</span></span>
<span><span>проверка:</span></span>
<span><span>(800-180):31=20</span></span>
<span><span>620:31=20</span></span>
<span><span>20=20</span></span>
<span><span>Удачи!</span></span>
<span><span>х=</span></span>
<span>
</span>
1)112.2:17*3=19.8 м отрезали в первый раз
2)112.2:17*7=46.2 м отрезали во второй раз
3)19.8+46.2=66 м отрезали за оба раза
А) 8/18 ; 15/18 ; 56/18
б) 70/80 ; 30/80 ; 42/80
(2)
а) 4/12 и 3/12
б) 10/16 и 3/16
в) 25/40 и 6/40
г) 16/72 и 21/72
299:(13+х)=26
13+х=299:26
х=11,5-13
х=-1,5