В самом начале задачи сказано. что каждый из 50 силен, умен, красив
Ответ: 50 парней
![9(3x-7)+3(8x-11)=3(9x+8)](https://tex.z-dn.net/?f=9%283x-7%29%2B3%288x-11%29%3D3%289x%2B8%29)
![27x-63+24x-33=27x+24](https://tex.z-dn.net/?f=27x-63%2B24x-33%3D27x%2B24)
![51x-96=27x+24](https://tex.z-dn.net/?f=51x-96%3D27x%2B24)
![51x-27x=24+96](https://tex.z-dn.net/?f=51x-27x%3D24%2B96)
![24x=120](https://tex.z-dn.net/?f=24x%3D120)
![x=120:24](https://tex.z-dn.net/?f=x%3D120%3A24)
![x=5](https://tex.z-dn.net/?f=x%3D5)
_______________________________________________________________________
(это проверка)
![9\cdot(15-7)+3\cdot(40-11)=3\cdot(45+8)](https://tex.z-dn.net/?f=9%5Ccdot%2815-7%29%2B3%5Ccdot%2840-11%29%3D3%5Ccdot%2845%2B8%29)
![9\cdot8+3\cdot29=3\cdot53](https://tex.z-dn.net/?f=9%5Ccdot8%2B3%5Ccdot29%3D3%5Ccdot53)
![72+87=159](https://tex.z-dn.net/?f=72%2B87%3D159)
![159=159](https://tex.z-dn.net/?f=159%3D159)
А) (40+5)+(20-10)=45+10=55
б) (100-70)-10=30-10=20
в) (12-12)+(10-5)=0+5=5
г) (40+29)-30=69-30=39
д) 80+(2+6)=80+8=72
е) (11+22)+50=33+50=83
- 56 < 55 ;
-1,02 > -1,2 .