1)
числитель:
(85 7/30 - 83 5/18 ) : 2 2/3 =
= (85 21/90 - 83 25/90 ) : 2 2/3 =
= 1 86/90 : (8/3) =
= 1 43/45 * 3/8 =
= (88 * 3) / (45 * 8) =
= (11*1) / (15*1) = 11/15
получилась дробь:
(11/15 ) / (1/25) = 11/15 : 1/25 =
= 11/15 * 25/1 =
= (11*5)/(3*1) = 55/3 =
= 18 1/3
2)
числитель:
(140 7/30 - 138 5/12) : 18 1/6 =
= (140 14/60 - 138 25/60) : (109/6) =
= 1 49/60 * 6/109 =
= 109/60 * 6/109 =
= (1*1)/(10*1) =
= 1/10 = 0,1
получилась дробь:
0,1 / ( 1/500) = 0,1 / 0,002 = 100/2 = 50
3)
числитель:
(95 7/30 - 95 5/18) * 2 1/4 + 373/1000 =
= (95 21/90 - 95 25/90 ) * 2 1/4 +0,373 =
= - 4/90 * 9/4 + 0,373 =
= - (1*1)/(10*1) + 0,373 =
= - 1/10 + 0,373 =
= - 0,1 + 0,373 =
= 0,373 - 0,100 =
= 0,273
получилась дробь:
0,273 / (1/5) = 0,273 : 0,2 = 273/200 = 1 73/200 = 1,365
4)
числитель:
(49 5/24 - 46 7/20) *2 1/3 +3/5 =
= (49 25/120 - 46 42/120) * (7/3) + 3/5 =
= 2 103/120 * 7/3 +3/5 =
= (343*7)/(120*3) + 3/5 =
= 2401/360 + 216/360 =
= 2617/360 = 7 97/360
получилась дробь:
(7 97/360 ) / (1/5) =
= 2617/360 * 5/1 =
= 2617/72 =
= 36 25/72