20.5 : (x + 399) = 0.05и(0.988 + x) ×2.5 = 4.87

Question

20.5 : (x + 399) = 0.05
и
(0.988 + x) ×2.5 = 4.87

Answer 1

20,5:(х+399)=0,05
х+399=20,5:0,05
х+399=410
х=410-399
х=11

0.988+x = 2.5
x-1.512 = 0
1x = 1.512
x = 1.512