Răspuns:
Explicație pas cu pas:
18.
a = 17b + 5
b = 1
a = 22
_________
a = 17b + 5
a + b = 365
17b + 5 + b = 365
18b = 365 - 5 = 360
b = 360 : 18 = 20
a = 365 - 20 = 345
_________
a = 17b + 5
a - b = 165
17b + 5 - b = 165
16b = 165 - 5 = 160
b = 160 : 16 = 10
a = 165 + 10 = 175
___________________________
19.
x*1/2 = 51
x = 2*51 = 104
_________
2*3*1/6 = 6/6 = 1
_________
2*p/100 = 5
p = 5*100/2 = 250%