Is 4:12 and 2:5 equivalent?

A33 gram sample of a substance that's used to detect explosives has a k-value of 0.1473. n = noekt no = initial mass (at time t = 0) n = mass at time t k = a positive constant that depends on the substance itself and on the units used to measure time t = time, in days

Matt had 5 library books. he checked out 1 additional book every week without retuening any books. whats the matching equation

What is the value of x? enter your answer in the box.