60*4+58= 298
3*60=180
29-17=12
298+180+12=490
<span>(4×b-16)÷2=10
4b - 16 = 10 * 2
4b - 16 = 20
4b = 20 + 16
4b = 36
b = 36 : 4
b = 9
проверка:( 4 * 9 - 16 ) : 2 = (36 - 16) : 2 = 20 : 2 = 10
10 = 10</span>
(36+48)+50=36+(48+50)
(524+308)+105=524+(308+105)
(12+800)+30=12+(800+30)
(361+152)+48=361+(152+48)
Вроде так