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2 years ago

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A total of 729 students participate in a school pep rally event. If every 30 minutes, 2/3 of the students leave, after 2 hours,

how many students will be still staying at the pep rally?

1 answer:

trapecia [35]2 years ago

5 0

There will be 9 students left at the prep rally after 2 hours.

After 30 minutes

Total Number of students = 729
2/3 of 729 = 486
Number of students left = 729 - 486 = 243

After 1 hour:

2/3 of 243 = 162
Number of students left = 243 - 162 = 81

After 1 hour 30 minutes :

2/3 of 81 = 54
Number of students left = 81 - 54 = 27

After 2 hours :

2/3 of 27 = 18
Number of students left = 27 - 18 = 9

Therefore, the Number of students left after 2 hours will be 9.

Learn more : brainly.com/question/18112348

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3 years ago

Consider the initial value problem y′+5y=⎧⎩⎨⎪⎪0110 if 0≤t<3 if 3≤t<5 if 5≤t<[infinity],y(0)=4. y′+5y={0 if 0≤t<311 i

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It looks like the ODE is

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In this case, we have

$\begin{cases}0&\text{for }0\le t$

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We can split the first term into partial fractions:

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Take the inverse transform of both sides, recalling that

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Answer:

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