Question

Afla numerele necunoscute. a) (123x-1278):149=36 b) 420:(160-25y)+24 X 7=180 c) {7200-[100-999999: (11000-z)] X 625} :225=7

Answer 1

a) (123x-1278):149=36
(123x-1278)=36x149
123x-1278=5364
123x=5364+1278
123x=6642
x=6642:123
x=54

b) 420:(160-25y)+24 X 7=180
 420:(160-25y)+168=180
 420:(160-25y)=180-168
 420:(160-25y)=12
160-25y=420:12
160-25y=35
25y=160-35
25y=125
y=125:25
y=5

c) {7200-[100-999999: (11000-z)] X 625} :225=7
{7200-[100-999999: (11000-z)] X 625} :225=7
{7200-[100-999999: (11000-z)] X 625}=7x225
7200-[100-999999: (11000-z)] X 625=1575
[100-999999: (11000-z)] X 625=7200-1575
[100-999999: (11000-z)] X 625=5625
100-999999: (11000-z)=5625:625
100-999999: (11000-z)=9
999999: (11000-z)=100-9
999999: (11000-z)=91
(11000-z)=999999:91
11000-z=10989
z=11000-10989
z=11