Aresearcher measures 200 counts per minute coming from a radioactive source at noon. at 3: 00pm, she finds that this has dropped to 25 counts per minute. what percentage of the original source will remain at 6: 00pm?

1.5% will remain at 6.00pm.

Step-by-step explanation:

The function for exponential decay is,

where,

y(t) = the future amount,

A = initial amount,

r = rate of growth,

t = time.

A researcher measures 200 counts per minute coming from a radioactive source at noon.

At 3:00pm, i.e after 3 hours,she finds that this has dropped to 25 counts per minute.

Putting the values,

-ve sign means the amount is decreasing.

As we have to find the amount at 6.00pm i.e after 6 hours, so

As number of bacteria can't be in decimal.

So the percentage will be,

typically if you want , you would actually put questions here for us to you. but hey, that's just me. maybe someone will magically answer the questions for you without knowing what they are.

addition

step-by-step explanation: