Пошаговое объяснение:
90/x=5
x = 90:5
x = 18
y/24=6
y = 6*24
y = 144
a/6=27
a = 27*6
a = 162
480/c=8
c = 480:8
c = 60
80×4=t+205
320 = t + 205
t = 320-205
t = 115
640÷(13-d)-78=82
640:(13-d)=82+78
640:(13-d)=160
13-d=640:160
13-d=4
d = 13-4
d=9
90×b=324+18×2
90b = 360
b = 360:90
b = 4
50×x+28=400-72
50x + 28 = 328
50x = 328 - 28
50x = 300
x = 300 : 50
x = 6
