Ask question

Ask question

All categories

3 years ago

13

Emily is entering a bicycle race for charity. Her mother pledges $0.10 for every 0.75 mile she bikes. If Emily bikes 18 miles, h

ow much will her mother donate?

1 answer:

Marta_Voda [28]3 years ago

7 0

Well you would have to add 0.10+0.75 then divide by 18 hope this helps

You might be interested in

Newton's law of cooling is:

Mnenie [13.5K]

Answer:

$t = \frac{ln(\frac{21}{59})}{-0.15}=6.887 hr$

So it would takes approximately 6.9 hours to reach 32 F.

Step-by-step explanation:

For this case we have the following differential equationÑ

$\frac{du}{dt}= -k (u-T)$

We can reorder the expression like this:

$\frac{du}{u-T} = -k dt$

We can use the substitution $w = u-T$ and $dw =du$ so then we have:

$\frac{dw}{w} =-k dt$

IF we integrate both sides we got:

$ln |w| = -kt +C$

If we apply exponential in both sides we got:

$w = e^{-kt} *e^c$

And if we replace w = u-T we got:

$u(t)= T + C_1 e^{-kt}$

We can also express the solution in the following terms:

$u(t) = (T_i -T_{amb}) e^{kt} +T_{amb}$

For this case we know that $k =-0.15 hr$ since w ehave a cooloing, $T_{i}= 70 F, T_{amb}=11F$ , we have this model:

$u(t) = (70-11) e^{-0.15t} +11$

And if we want that the temperature would be 32F we can solve for t like this:

$32 = 59 e^{-0.15 t} +11$

$21=59 e^{-0.15 t}$

$\frac{21}{59} = e^{-0.15 t}$

If we apply natural logs on both sides we got:

$ln (\frac{21}{59}) =-0.15 t$

$t = \frac{ln(\frac{21}{59})}{-0.15}=6.887 hr$

So it would takes approximately 6.9 hours to reach 32 F.

7 0

3 years ago

Help me please please

Tresset [83]

Answer:

hope its help u

Step-by-step explanation:

$let \: the \: angle \: be \: \alpha \\ \tan( \alpha ) = \frac{p}{b} \\ \tan(32) = \frac{25}{x} \\ 0.62486= \frac{25}{x } \\ x = \frac{25}{0.62486} \\ x = 40$

4 0

1 year ago

Write an equation that is perpendicular to y = 2x + 5 and passes through (3 , -2)

Maslowich

To find the perpendicular line, we need to find the negative inverse slope.

y = -1/2x - 2

This line also passes through the point since both have the y intercept / value of -2.

Hope this helps!

3 0

3 years ago

Student council hosted a bake sale of the 40 items brought to sale 18 were brownies. what percent of the bake sale were Brownies

LuckyWell [14K]

Answer:

45 percent were brownies :)

7 0

3 years ago

C. The number of men in a community is 2,400. If the ratio of women to men in the community is 5:4,

Ivahew [28]

Answer:

women : men

5. : 4

x. : 2400

x = 3000

i) 3000 + 2400= 5400

ii) 3000

iii) 3000 - ( 2400+400) = 200

7 0

2 years ago