15+(59-36)=15+23=38
(47+42)-68=89-68=21
41-(73-32)=41-41=0
(72+16)+10=88+10=98
4а+2(3в)-6в+10=12
4а+6в-6в+10=12
4а+10=12
4а=12-10
4а=2
а=2
2.1/3x-2.1/3=2.1/3
2.1/3x=2.1/3+2.1/3
2.1/3x=4.2/3
x=4.2/3:2.1/3
x=2
Ответ:2
122-7=115
190-6=184
наибольший общий делитель - 23
в городе 23 школы.
<span>2/3</span> × <span>9/10</span> = <span>2·93·10</span> = <span>1830</span> = <span>3·65·6</span> = <span>3/5</span><span> = 0.6
</span>
2 <span>3/5</span> × 1 <span>9/26</span> = 3 <span>1/2</span><span> = 3.5
</span>
1) 15:5=3 (км) - 1 часть
2) 3*3= 9 (км) - по лесу