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3 years ago

Sophia is saving money for a new bicycle. The bicycle will cost at least $623. Sophia makes $8.22 per hour.

Mathematics

2 answers:

valina [46]3 years ago

7 0

Answer:

C. $8.22 h\geq$ $ 623

Step-by-step explanation:

We are given that Sophia is saving money for a new bicycle.

The bicycle will cost atleast $623.

Sophia makes $8.22 per hour.

We have to find the inequality that could be used to find the number of hours Sophia needs to work to make enough money to buy a new bicycle.

Let Sophia works h hours to make enough money to buy a new bicycle.

Sophia makes money per hour =$8.22

Total money made by Sophia in h hours = $8.22 h$

According to question

$8.22 h\geq$ $623

Hence, option C is true.

Luda [366]3 years ago

3 0

$8.22h greater than or equal to $623

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Where:

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This equation is solved as follows:

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$c = 30 + C\cdot e^{-\frac{t}{10} }$

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$c_{o} = 0.167\,\frac{pd}{gal}$

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$0.167 = 30 + C$

$C = -29.833$

The solution of the differential equation is:

$c(t) = 30 - 29.833\cdot e^{-\frac{t}{10} }$

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$m_{salt} = V_{tank}\cdot c(t)$

$m_{salt} = (60)\cdot (30 - 29.833\cdot e^{-\frac{t}{10} })$

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harkovskaia [24]

Answer:

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Step-by-step explanation:

Given

See attachment for model

Required

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$\frac{4}{7}\times\frac{13}{9} = \frac{52}{63}$

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3 years ago