All categories

3 years ago

Please answer the question

Mathematics

1 answer:

Lunna [17]3 years ago

4 0

A since 19 x 29= 551 and 551/375 is around 1.5

You might be interested in

1. 8x – 4 = 12x + 12

olga_2 [115]

7(x-2) +3x=46
7x-14+3x=46
10x-14=46
10x=60
X=6

3 0

3 years ago

A tank initially contains 60 gallons of brine, with 30 pounds of salt in solution. Pure water runs into the tank at 3 gallons pe

adoni [48]

Answer:

the amount of time until 23 pounds of salt remain in the tank is 0.088 minutes.

Step-by-step explanation:

The variation of the concentration of salt can be expressed as:

$\frac{dC}{dt}=Ci*Qi-Co*Qo$

being

C1: the concentration of salt in the inflow

Qi: the flow entering the tank

C2: the concentration leaving the tank (the same concentration that is in every part of the tank at that moment)

Qo: the flow going out of the tank.

With no salt in the inflow (C1=0), the equation can be reduced to

$\frac{dC}{dt}=-Co*Qo$

Rearranging the equation, it becomes

$\frac{dC}{C}=-Qo*dt$

Integrating both sides

$\int\frac{dC}{C}=\int-Qo*dt\\ln(\abs{C})+x1=-Qo*t+x2\\ln(\abs{C})=-Qo*t+x\\C=exp^{-Qo*t+x}$

It is known that the concentration at t=0 is 30 pounds in 60 gallons, so C(0) is 0.5 pounds/gallon.

$C(0)=exp^{-Qo*0+x}=0.5\\exp^{x} =0.5\\x=ln(0.5)=-0.693\\$

The final equation for the concentration of salt at any given time is

$C=exp^{-3*t-0.693}$

To answer how long it will be until there are 23 pounds of salt in the tank, we can use the last equation:

$C=exp^{-3*t-0.693}\\(23/60)=exp^{-3*t-0.693}\\ln(23/60)=-3*t-0.693\\t=-\frac{ln(23/60)+0.693}{3}=-\frac{-0.959+0.693}{3}= -\frac{-0.266}{3}=0.088$

5 0

3 years ago

Find the volume of a cone with a diameter of 7 inches and a height that is 4 times the radius. Use 3.14 for pi, and round your a

Tatiana [17]

Answer:

179.50 $in^{3}$

Step-by-step explanation:

The equation for volume of a cone is:

$V=\pi *r^{2} *\frac{h}{3}$

The radius is half of the diameter so r= 3.5 in

The height is 4 times the radius so h=14

$V=3.14*3.5^{2} * \frac{14}{3}$

V= 179.50 $in^{3}$

7 0

3 years ago

Read 2 more answers

The table shows a linear function. x -5,-4,-3,-2,-1, 0, 1, 2, 3. on top row f(x) -11, -3, 5, 13, 21, 29, 37, 45, 53. on bottom r

NARA [144]

Wouldn’t the inputs be 4 and 5? I could wrong though

7 0

3 years ago

Read 2 more answers

What is the value of 6(2b-4) when b=5?

s2008m [1.1K]

Replace b with 5:

6(2(5)-4)

Simplify:

6(10-4)

Subtract:

6(6)

Multiply to get the answer: 36

The answer is 36

8 0

3 years ago