Solve for t q = (s+t) (r/2)

Isolate the factor (s+t) : s+t = q / (r/2). This simplifies to s+t=2q/r.

Subtract s from both sides to isolate t:

t=2q/r - s (Answer).

Alternatively, mult. both sides of q = (s+t) (r/2) by 2 to eliminate the fraction r/2:

2q = (s+t) (r) = sr + tr

Subtract sr from both sides: 2q - sr = tr

Divide both sides by r to obtain an equation for t: (2q/sr) - (sr/r) = t,

or (2q/sr) - s = t