18/5 + 8/7 : 5/28 = 18/5 + 8/7 • 28/5 = 18/5 + 32/5 = 50/5 = 10
5816-810:4+812=6425,5
1)810:4=202,5
2)5816-202,5=5613,5
3)5613,5+812=6425,5
1) 400:50 = 8
2) 8 + 298 = 306
3) 306 : 6 = 51
4) 51 + 87= 138
Ответ: 138
<span>17830,625
≈ </span><span>17830,63 ≈</span><span> 17830,6 ≈</span><span><span> 17831</span></span>
7*(x-0,3)=3,5*(x+2,4)
7x-2,1=3,5x+8,4
7x-3,5x=8,4+2,1
3,5x=10,5
x=10,5:3,5
x=3