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I am very confused on what to do.Can someone help me?

I am very confused on what to do.Can someone help me?-example-1
User Artxur
by
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1 Answer

6 votes

Answer:

739 m²

Explanation:


\boxed{\begin{minipage}{9 cm}\underline{General form of an Exponential Equation}\\\\$y=ab^x$\\\\where:\\\phantom{ww}$\bullet$ $a$ is the initial value ($y$-intercept). \\ \phantom{ww}$\bullet$ $b$ is the base (growth/decay factor) in decimal form.\\\end{minipage}}

The given scenario can be modelled as an exponential equation.

Let y be the area the fire covers (in meters squared).

Let x by the time (in hours).

If the fire currently covers an area of 32 m² then the initial value, a, is 32.

If the area covered by the fire increases by 17% each hour, then the growth factor, b, is 1.17 (since an increase of 17% is 117% of the previous amount).

Therefore:

  • a = 32
  • b = 1.17

Substitute the values of a and b into the exponential formula:


y=32(1.17)^x

To find the area that the first covers in 20 hours' time, simply substitute x=20 into the equation:


\implies y=32(1.17)^(20)


\implies y=32(23.1055991...)


\implies y=739.37917...

Therefore, the area the fire will cover in 20 hours' time is 739 m² (nearest 1 m²).

User Nomas Prime
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