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4 years ago

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(c) Jessica is training for the 400 meter relay race. She has trained three times this week and took 46, 52, and 54 seconds on h

er 400 meter races. What is the maximum amount of time she can spend on her fourth race to average at most 51 seconds? Show your work and justify your steps.

1 answer:

cestrela7 [59]4 years ago

4 0

Answer: 56 seconds or less

Step-by-step explanation:

3(46 + 52 + 54) $\leq$ 400 - x

Combine

3(152) $\leq$ 400 - x

Simplify

456 $\leq$ 400 - x

Subtract 456 from both sides

0 $\leq$ -56 - x

Add x to both sides

x $\leq$ 56 seconds

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anastassius [24]

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2/3 + 2/3 = 4/3

Note that the answer gotten is an “improper fraction”, because the numerator is greater than the denominator. Simplify.

4/3 = 3/3 + 1/3

Divide: 3/3 = 1

1 + 1/3 = 1 1/3

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2 years ago

Given circle O, angle A has a measure of 36° and the radius is 10 cm, find the area of sector BOC.

Fed [463]

Answer:

The area of the sector BOC is A' = 31.4 $cm^{2}$

Step-by-step explanation:

Radius of the circle = 10 cm = 0.1 m

Angle of sector $\theta$ = 36°

Area of the circle A = $\pi r^{2}$

A = 3.14 × $0.1^{2}$ = 0.0314 $m^{2}$

Now area of the sector BOC is

$A' = A (\frac{\theta}{360} )$

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4 years ago

Solve the Differential equation 2(y-4x^2) dx + x dy = 0

padilas [110]

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$\Psi_{xy}=(2y-8x^2)_y=2$

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so the ODE is now exact.

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$\Psi_y=x^2=x^2+f_y\implies f_y=0\implies f(y)=C$

So the ODE has solution

$\Psi(x,y)=x^2y-2x^4+C=C$

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