1) 560*65=36.400
2) 36.400:700=52
3) 6000-52=5.948
P.S. Надеюсь все понятно.
1/2- 1 3/5у=4 1/2-3у
0,5-1,6y=4,5-3y
-1,6y+3y=4,5-0,5
1,4y=4
y=4:1,4
y=2 6/7
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1/2- 1 3/5у=4 1/2-3у
-1 3/5y+3y=4 1/2-1/2
1 2/5y=4
y=4:1 2/5
y=4*5/7
y=20/7=2 6/7
(580-х) / 4 = 100/1
580 - х = 4 * 100
-х = 400 - 580
х = 180
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2 1/5+3 2/3=2 3/15+3 10/15=5 13/15
3 6/7-2 8/9=3 54/63-2 56/63=2 117/63-2 56/63=61/63
2 1/3=1 2/3