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3 years ago

The temperature changed at a rate of -3 degrees per hour. How long did it take for the temperature change to be -18

Mathematics

1 answer:

DIA [1.3K]3 years ago

4 0

Answer:

6 Hours

Step-by-step explanation:

If the rate is -3, that means there is an hourly change of 3 degrees. To get to 18, you must divide 18 by 3.

18÷3=6

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Please help!! I really need help! 4. Solve using 1 transformation 3/4a=24 please show work and the 3/4 is a fraction.

Cloud [144]

3/4a=24

first divide 3/4 from 24

getting...

a=32

To test this put 32 in the place of a

3/4(32)=24

so a=32

An easier way to do this is make the fraction a decimal to do so divide them as following 3/4 would be divided as 3/4 making it .75

7 0

3 years ago

A rectangular storage container with an open top is to have a volume of 10 m3. The length of this base is twice the width. Mater

noname [10]

Answer:

$ 327.08

Step-by-step explanation:

Let w be the width ( in meters ) of the container,

⇒ Length of the container = 2w,

If h be the height of the container,

So, the volume of the container = length × width × height

= 2w × w × h

= 2w² h

According to the question,

$2w^2h=10$

$\implies h=\frac{10}{2w^2}=\frac{5}{w^2}$

Now, the area of the base = length × width

$=2w^2$

Area of sides = 2 × length × height + 2 × width × height

$=2\times 2w\times h+2\times w\times h$

$=4w\times \frac{5}{w^2}+2w\times \frac{5}{w^2}$

$=\frac{20}{w}+\frac{10}{w}$

$=\frac{30}{w}$

Since, material for the base costs $20 per square meter and material for the sides costs $12 per square meter,

Hence, total cost,

$C(w) = 2w^2\times 20 +\frac{30}{w}\times 12$

$C(w)=40w^2+\frac{360}{w}$

Differentiating with respect to w,

$C'(w) = 80w - \frac{360}{w^2}$

Again differentiating with respect to w,

$C''(w) = 80 +\frac{720}{w^3}$

For maxima or minima,

C'(w) = 0

$80w - \frac{360}{w^2}=0$

$80w^3-360=0$

$80w^3=360$

$\implies w=\sqrt[3]{\frac{360}{80}}=1.65096362445\approx 1.651$

For w = 1.651, C''(w) = positive,

Thus, cost is minimum for width 1.651 meters,

And, the minimum cost = C(1.651) = $40(1.651)^2+\frac{360}{1.651}=\$327.081706869\approx \$ 327.08$

3 0

4 years ago

Good afternoon help me plz just 2 question 10 points

Tom [10]

Supplementary angles have sum = 180
m<TUW = 31
m<TUV = 180 - 31 = 149

answer is 149 (last choice)

second picture:
answer is vertical angles (2nd choice)

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3 years ago

The midpoint between y and k is d. What is y?

iren2701 [21]

Answer:

k-d

Step-by-step explanation:

if y is one point and k is another but d is in the middle, to find y i would assume you would just subtract d from k so k-d=y

7 0

4 years ago

mrs pulido has 12 times as many soccer ball as bowling balls. the total number of soccer balls is 78. how many soccer balls does

Harlamova29_29 [7]

72 because 12*6=72. 72+6=78

6 0

3 years ago

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