Сократить дроби: 14/21 55/77 140/210 12/30 81/270 105/165 24/60 75/450 144/360 35/105 135/180 240/560

Question

Математика: Сократить дроби: 14/21 55/77 140/210 12/30 81/270 105/165 24/60 75/450 144/360 35/105 135/180 240/560

begk55 · Accepted Answer

( 3 - 1.2a) / 4 = 0
3 - 1,2а = 0 * 4
3 - 1,2а = 0
-1,2а = - 3
а = - 3 : (-1,2) = 30/12
а = 2,5
проверим :
(3 - 1,2 * 2,5) / 4 = (3-3)/4 = 0/4 = 0

(3 - 1,2а)/4 = - 1
3 - 1,2а = - 1 * 4
3 - 1,2а = -4
-1,2а = - 4 - 3
-1,2а= - 7
а= - 7 : (-1,2) = 70/12 =35/6
а= 5 5/6
проверим:
( 3 - 1,2 * 5 5/6) / 4 = ( 3 - 6/5 * 35/6)/4 = (3-7)/4 = -4/4 = -1

(3 - 1,2а) / 4 = - 1/12
3 - 1,2а = - 1/12 * 4
3 - 1,2а= - 4/12
3 - 1,2а= - 1/3
- 1,2а= - 1/3 - 3
- 1,2а = - 3 1/3
а =- 3 1/3 : (-1,2) = (-10/3) : (- 6/5) = (10*5)/(3*6) = (5*5)/(3*3) = 25/9
а= 2 7/9
проверим:
(3 - 1,2 * 2 7/9) / 4 = (3 - 6/5 * 25/9) / 4 = (3 - 3 1/3) / 4 =
= - 1/3 : 4 = - 1/3 * 1/4 = - 1/12

MOGZ ответил