All categories

2 years ago

Kelly read 30 pages of her 300-page book in 6 hours. at this rate, how long will it take her to read the entire book?

Mathematics

2 answers:

Tanya [424]2 years ago

7 0

Answer:

60 hours

Step-by-step explanation:

300 ÷ 30 = 10

10 x 6 = 60

Hope this helps :)

musickatia [10]2 years ago

6 0

Answer: 60 hours

Step-by-step explanation:

30=300- times 10

6=_60_

You might be interested in

Solve: 92x + 1 = 93x – 2

vichka [17]

Answer:

x equals 3 :) if i helped, please give brainliest!

Step-by-step explanation:

6 0

3 years ago

Read 2 more answers

4x 1 1/5= write the product as a mixed number

Pepsi [2]

I believe the answer is
2 and 1/5

4 0

3 years ago

Read 2 more answers

Help plea i am beg screenshot in

stiv31 [10]

Answer:

SA = 105 in^2

Step-by-step explanation:

To find surface area, find the area of all the shapes and add it all together. This shape has 4 triangle faces. They are all the same. So we can find one of them and times by 4.

Area of a triangle:

A = 1/2b•h

= 1/2• 5 • 8

= 1/2 • 40

= 20

One triangle has area 20, so times by 4 (bc four triangles)

4•20

= 80

Area of square 5•5

= 25

Add the areas:

80 + 25

= 105 sq in

7 0

2 years ago

A 500-gallon tank initially contains 220 gallons of pure distilled water. Brine containing 5 pounds of salt per gallon flows int

Wittaler [7]

Answer: The amount of salt in the tank after 8 minutes is 36.52 pounds.

Step-by-step explanation:

Salt in the tank is modelled by the Principle of Mass Conservation, which states:

(Salt mass rate per unit time to the tank) - (Salt mass per unit time from the tank) = (Salt accumulation rate of the tank)

Flow is measured as the product of salt concentration and flow. A well stirred mixture means that salt concentrations within tank and in the output mass flow are the same. Inflow salt concentration remains constant. Hence:

$c_{0} \cdot f_{in} - c(t) \cdot f_{out} = \frac{d(V_{tank}(t) \cdot c(t))}{dt}$

By expanding the previous equation:

$c_{0} \cdot f_{in} - c(t) \cdot f_{out} = V_{tank}(t) \cdot \frac{dc(t)}{dt} + \frac{dV_{tank}(t)}{dt} \cdot c(t)$

The tank capacity and capacity rate of change given in gallons and gallons per minute are, respectivelly:

$V_{tank} = 220\\\frac{dV_{tank}(t)}{dt} = 0$

Since there is no accumulation within the tank, expression is simplified to this:

$c_{0} \cdot f_{in} - c(t) \cdot f_{out} = V_{tank}(t) \cdot \frac{dc(t)}{dt}$

By rearranging the expression, it is noticed the presence of a First-Order Non-Homogeneous Linear Ordinary Differential Equation:

$V_{tank} \cdot \frac{dc(t)}{dt} + f_{out} \cdot c(t) = c_0 \cdot f_{in}$ , where $c(0) = 0 \frac{pounds}{gallon}$ .

$\frac{dc(t)}{dt} + \frac{f_{out}}{V_{tank}} \cdot c(t) = \frac{c_0}{V_{tank}} \cdot f_{in}$

The solution of this equation is:

$c(t) = \frac{c_{0}}{f_{out}} \cdot ({1-e^{-\frac{f_{out}}{V_{tank}}\cdot t }})$

The salt concentration after 8 minutes is:

$c(8) = 0.166 \frac{pounds}{gallon}$

The instantaneous amount of salt in the tank is:

$m_{salt} = (0.166 \frac{pounds}{gallon}) \cdot (220 gallons)\\m_{salt} = 36.52 pounds$

3 0

3 years ago

HELP ASAP!! What is the length of PQ? 12 km 16 km 18 km 20 km

natima [27]

20 km is the correct answer

4 0

3 years ago

Read 2 more answers