A scientist measures the initial amount of Carbon-14 in a substance to be 25 grams.

Mathematics

2 answers:

galina1969 [7]3 years ago

7 0

In 386750.36 years the Carbon - 14 will be 20 g in the substance

Step-by-step explanation:

Here A = 20 g

The given equation is,

A= 25e - 0.000124t

We need to find the value of t

20 = 25e - 0.000124t

20 - 25e = - 0.000124t

25e - 20 = 0.000124t

(25e - 20 ) / 0.000124 = t

t = (25e - 20) / 0.000124

t = (65.957 - 20) / 0.000124

t = 45.957 / 0.000124

t = 386750.36 years

Brums [2.3K]3 years ago

3 0

Answer:

ln (0.8)/-0.00012 years

Step-by-step explanation:

We can solve the equation as shown below.

\begin{aligned}25\cdot e^{-0.00012t}&=20\\\\ e^{-0.00012t}&=0.8\\\\ -0.00012t&=\ln\left(0.8\right)\\\\ t&=\dfrac{{\,\ln\left(0.8\right)}}{-0.00012}\\\\ \end{aligned}

25⋅e

−0.00012t

=20

=0.8

=ln(0.8)

−0.00012

ln(0.8)

It will take \dfrac{{\,\ln\left(0.8\right)}}{-0.00012}

−0.00012

ln(0.8)

start fraction, natural log, left parenthesis, 0, point, 8, right parenthesis, divided by, minus, 0, point, 00012, end fraction years for the amount of Carbon-141414 remaining in the substance to be 20\text{ g}20 g20, start text, space, g, end text.

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andreyandreev [35.5K]

Answer:

There are 2450 ways.

Step-by-step explanation:

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