Question 901035
You *could* use trial and error, guessing what the number is and plugging it in until you get the right answer, or you could use math :-)
B + C = 1.05
B = C + 1.00
Substitute the value of B from the second equation into the first.
B + C = $1.05
(C+1.00)+ C = $1.05
2C + 1.00 = $1.05
Subtract a dollar from each side
2C = .05
Divide each side by 2
C = .025
Each cork costs 2.5 cents.  The bottle costs a dollar more than that, or one dollar and 2.5 cents.
.025 + 1.025 = $1.05
That might be a difficult one for trial and error since it contains a half cent.