(50+5)-(30+3)=22
(70+8)-(20+7)=51
(500+300)-(200+10)=690
(700+6)-(300+5)=401
3х + 8х = 99
х = 9
первое число: 3х = 3*9 = 27
второе число: 8х = 8*9 = 72
Ответ: 1944
1. 802–(414–82)+(395–109)=756
1)414–82=332
2)395–109=286
3)802–332=470
4)470+286=756
2.(119+78)–(540–509)+405=571
1)119+78=197
2)540–509=31
3)197-31=166
4)166+405=571
3. 3•(421-325):2=144
1)421-325=96
2)3•96=288
3)288:2=144
4.980-(745-199):2=217
1)745-199=546
2)980-546=434
3)434:2=217
1) 2 ( 1/2 ) = 250 %
2) 4 ( 1/5 ) = 420 %
3) 5 ( 1/10 ) = 510 %
4) 7 ( 1/100 ) = 701 %