(23 1/21 : 1 3/7 - 5,5 ) : 3,19 - 1 17/18=
выражением:
= (484/21 * 7/10 -5,5) :3,19 - 1 17/18 =
= ((242/15) - (11/2) ) : 3,19 - 17/18 =
= ((484 -165)/30 ) : (319/100) - 1 17/18=
= 319/30 * 100/319 - 1 17/18 =
= 10/3 - 35/18 =
= (60-35)/18 = 25/18 =
= 1 7/18
По действиям:
1) 23 1/21 : 1 3/7 = 484/21 : 10/7 =
= 484/21 * 7/10 = (242*1) / (3*5) = 242/15 =16 2/15
2) 16 2/15 - 5,5 = 16 4/30 - 5 15/30 = 10 19/30
3) 10 19/30 : 3,19 = 319/30 : 319/100 =
= 319/30 * 100/319 = 10/3 = 3 1/3
4) 3 1/3 - 1 17/18 = 3 6/18 - 1 17/18 = 1 7/18
Ответ : 1 7/18.
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