Răspuns:
Explicație pas cu pas:
26×15+400:100+y:5 - 85=408
y: 5 = a =>
26×15+400:100+a -85 = 408 =>
390 + 4 + a -85 = 408 =>
394 +a = 408+85 =>
394+a = 493 =>
a = 493-394
a = 99
y:5 = 99 => y = 99·5 => y = 495
30×28:6+y×3-40:10=190 ; y×3 = b =>
840:6 + b -4 = 190 =>
140 + b -4 = 190 =>
140+b = 190+4 =>
b = 194-140 => b = 54 =>
y×3 =54 => y = 54:3 => y = 18
#copaceibrainly
