An element with mass 570 grams decays by 26.9% per minute. How much of the element is remaining after 14 minutes, to the nearest 10th of a gram?

7.1

Step-by-step explanation:

Exponential Functions:

y=ab^x

y=ab  

x

a=\text{starting value = }570

a=starting value = 570

r=\text{rate = }26.9\% = 0.269

r=rate = 26.9%=0.269

\text{Exponential Decay:}

Exponential Decay:

b=1-r=1-0.269=0.731

b=1−r=1−0.269=0.731

\text{Write Exponential Function:}

Write Exponential Function:

y=570(0.731)^x

y=570(0.731)  

x

Put it all together

\text{Plug in time for x:}

Plug in time for x:

y=570(0.731)^{14}

y=570(0.731)  

14

y= 7.091174

y=7.091174

Evaluate

y\approx 7.1

y≈7.1

round

The sales person is making 3% so, we would simply multiply $1400 by .03

1400*.03

=$42

They made $42 dollars on a $1400 sale, pretty lousy if you ask me.