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2 years ago

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Of 100 students, 30 can speak French, 10 can speak German, and 6 can speak both French and German. If a student is picked at ran

dom, what is the probability that he or she can speak French or German? (Enter your probability as a fraction.)

1 answer:

joja [24]2 years ago

6 0

Answer:

the correct answer would be 1,800

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5 cups to 8 cups <br> identify the percent

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Well I am going to guess and i don't know if it right but 156.25ml

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Mabel spends 444 hours to edit a 333 minute long video. She edits at a constant rat\\\\\\\\\\\\\\e. How long does Mabel spend to

mestny [16]

Mabel spends 4 hours editing a 3 minute video. she edits at a constant rate. how long does mabel spend to edit a 9 minute video?

she spends 4 hours on a 3 minute video
so there are 60 minutes in an hour
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so she spent 240 minutes on a 3 minute video
3 divided by 240
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so divide 9 minutes by her constant rate
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2 years ago

6. Nicole deposits $2,136 in a såvings account paying 5% interest rate. To the

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Step-by-step explanation:

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2 years ago

Show your work <br> Solve multi step equation <br> 4d-3-2d=-15

Fed [463]

I believe this is how you do it

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3 years ago

Read 2 more answers

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Archy [21]

(a) If the particle's position (measured with some unit) at time <em>t</em> is given by <em>s(t)</em>, where

$s(t) = \dfrac{5t}{t^2+11}\,\mathrm{units}$

then the velocity at time <em>t</em>, <em>v(t)</em>, is given by the derivative of <em>s(t)</em>,

$v(t) = \dfrac{\mathrm ds}{\mathrm dt} = \dfrac{5(t^2+11)-5t(2t)}{(t^2+11)^2} = \boxed{\dfrac{-5t^2+55}{(t^2+11)^2}\,\dfrac{\rm units}{\rm s}}$

(b) The velocity after 3 seconds is

$v(3) = \dfrac{-5\cdot3^2+55}{(3^2+11)^2} = \dfrac{1}{40}\dfrac{\rm units}{\rm s} = \boxed{0.025\dfrac{\rm units}{\rm s}}$

(c) The particle is at rest when its velocity is zero:

$\dfrac{-5t^2+55}{(t^2+11)^2} = 0 \implies -5t^2+55 = 0 \implies t^2 = 11 \implies t=\pm\sqrt{11}\,\mathrm s \imples t \approx \boxed{3.317\,\mathrm s}$

(d) The particle is moving in the positive direction when its position is increasing, or equivalently when its velocity is positive:

$\dfrac{-5t^2+55}{(t^2+11)^2} > 0 \implies -5t^2+55>0 \implies -5t^2>-55 \implies t^2 < 11 \implies |t|$

In interval notation, this happens for <em>t</em> in the interval (0, √11) or approximately (0, 3.317) s.

(e) The total distance traveled is given by the definite integral,

$\displaystyle \int_0^8 |v(t)|\,\mathrm dt$

By definition of absolute value, we have

$|v(t)| = \begin{cases}v(t) & \text{if }v(t)\ge0 \\ -v(t) & \text{if }v(t)$

In part (d), we've shown that <em>v(t)</em> > 0 when -√11 < <em>t</em> < √11, so we split up the integral at <em>t</em> = √11 as

$\displaystyle \int_0^8 |v(t)|\,\mathrm dt = \int_0^{\sqrt{11}}v(t)\,\mathrm dt - \int_{\sqrt{11}}^8 v(t)\,\mathrm dt$

and by the fundamental theorem of calculus, since we know <em>v(t)</em> is the derivative of <em>s(t)</em>, this reduces to

$s(\sqrt{11})-s(0) - s(8) + s(\sqrt{11)) = 2s(\sqrt{11})-s(0)-s(8) = \dfrac5{\sqrt{11}}-0 - \dfrac8{15} \approx 0.974\,\mathrm{units}$

7 0

2 years ago