The the amount of the original gold-198 that remains after 5.4 days is one-quarter.
Half-life is the time required or taken for half the amount of matter present in a given substance to vanish or decay.
The half-life of gold-198 is 2.7 days.
After, 5.4 days, the gold would have undergone two half-lives.
The amount of matter remaining = 1/2 * 1/2 = 1/4
Therefore, the amount of the original gold-198 that remains is one-quarter.
Learn more about half-life at: https://brainly.com/question/26689704
#SPJ1