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emmainna [20.7K]

3 years ago

5

a teacher had 57.72 in his checking account. he made a deposit of 209.54. then he wrote a check for 72.00 and another check for

27.50. what is the new balance in his checking account?

1 answer:

vodka [1.7K]3 years ago

8 0

Your answer is 167.76 you had to add 209.54 to 57.72 then subtract 72.00 and 27.50 from that answer

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A common inhabitant of human intestines is the bacterium Escherichia coli, named after the German pediatrician Theodor Escherich

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Step-by-step explanation:

From the formula of bacterial population,

$A_{t}=A_{0}e^{kt}$

Where $A_{t}$ = Bacterial population after time t

$A_{0}$ = Initial population

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Time t = 20 minutes = $\frac{1}{3}$ hours

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Since k = 3ln(2)

$A_{t}=A_{0}e^{3t(ln2)}$

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Now our expression will be $A_{t}=A_{0}(2^{3t} )$

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$A_{6}=50\times (262144)=13107200$

d). We can get the rate of growth by finding derivative of the expression

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$1000000=50(2^{3t} )$

$2^{3t}=20000$

3t(ln2) = ln(20000)

t = $\frac{ln(20000)}{3(ln2)}$

t = $\frac{9.90349}{2.07944}=4.76$ hours

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