В решении.
Пошаговое объяснение:
Сразу по действиям:
1.
1) -0,2 * 0,3 = -0,06;
2) -0,06 - 0,1 = -0,16;
3) -4,9 : (-0,16) = 30,625;
2.
1) 3 17/36 - 6 7/12 = -(6 21/36 - 3 17/36) = -3 4/36 = -3 1/9;
2) -3 1/9 : 0,4 = -28/9 : 2/5 = -(28 * 5)/(9 * 2) = -70/9;
3) 4 1/3 : (-0,65) = 13/3 : (-13/20) = -(13 * 20)/(3 * 13) = -20/3;
4) -70/9 - 20/3 = -(70 + 60)/9 = -130/9 = -14 4/9.
3.
1) 49 * (-45) = -2205;
2) 2 * (-3) = -6;
3) 84 - (-6) = 84 + 6 = 90;
4) -14 * 90 = -1260;
5) -2205 : -1260 = 1,75.
Или: (быстрее):
1) 2 * (-3) = -6;
2) 84 - (-6) = 84 + 6 = 90;
3) (49 * (-45))/(-14 * 90) =
сократить 49 и -14 на 7; -45 и 90 на 45;
= (7 * (-1))/(-2 * 2) = -7/-4 = 1,75.
4.
1) -4 3/7 - 1 2/3 = -(4 9/21 + 1 14/21) = -5 23/21 = -6 2/21;
2) -6 2/21 * 2,1 = -128/21 * 2,1 = -128/10 = -12,8;
3) 18 - 2,64 = 15,36;
4) 15,36 : (-8/3) = 15 9/25 : (-8/3) = 384/25 * (-8/3) = -(48 * 3)/25 =
= -144/25 = -5,76.
5) -12,8 : (-5,76) = -12 4/5 : (-5 19/25) =
= -64/5 : (-144/25) = (64 * 25)/(5 * 144) = 20/9 = 2 2/9.
Пошаговое объяснение:
А)
1) -0,2 * 0,3 = -0,06
2) -0,06 - 0,1 = -0,16
3) -4,9 : (-0,16) = 30,625
Б)
1) 3. 17/36 - 6. 7/12 = 3. 17/36 - 6. 21/36 = -3. 4/36 = -3. 1/9
2) -3. 1/9 : 0,4 = -3. 1/9 : 4/10 = -28/9 * 10/4 = -7/9 * 10/1 = -70/9 = -7. 7/9
3) 4. 1/3 : (-0,65) = 4. 1/3 : (-65/100) = 13/3 : (-13/20) = 13/3 * (-20/13) = -20/3 = -6. 2/3
4) -7. 7/9 + (-6. 2/3) = -7. 7/9 - 6. 2/3 = -7. 7/9 - 6. 6/9 = -13. 13/9 = -14. 4/9
В)
1) 49 * (-45) = -2205
2) 2 * (-3) = -6
3) 84 - (-6) = 84 + 6 = 90
4) -14 * 90 = -1260
5) -2205 : (-1260) = 1,75
Г)
1) -4. 3/7 - 1. 2/3 = -4. 9/21 - 1. 14/21 = -5. 23/21 = -6. 2/21
2) -6. 2/21 * 2,1 = -6. 2/21 * 2. 1/10 = -128/21 * 21/10 = -128/10 = -12,8
3) 18 - 2,64 = 15,36
4) 15,36 : (-1. 3/5) = 15,36 : (-8/5) = 15,36 : (-1,6) = -9,6
5) -12,8 : (-9,6) = -12. 8/10 : (-9. 6/10) = -128/10 : (-96/10) = -128/10 * (-10/96) = 128/96 = 1. 32/96 = 1. 1/3
14,788<-14,7
0>-13
14/18=не делится