All categories

2 years ago

Bernie’s estimated that 69% of 242 is 168 is her estimate reasonable

Mathematics

1 answer:

asambeis [7]2 years ago

7 0

Answer:

Yes it is.

Step-by-step explanation:

Best way is to use percentages you know when estimating.

We know 50% is half.

50% of 242 is 121.

So it has to be more than 121.

10% of 242 is 24.2 so add that to 121 and you get 145.2

You are 60% so far. You just need 9% more.

Add another 10% which is 24.2 and you get 169.4, which is over but we used 10% instead of 9% so the estimate is reasonable and close.

You might be interested in

Find the circumference of the circle in terms of pi

madam [21]

It's 78π inches so probably d.

3 0

2 years ago

PLS TRY TO ANSWER ASAP.

Harrizon [31]

Answer:

0.075 m/min

Explanation:

You need to use derivatives which is an advanced concept used in calculus.

1. Write the equation for the volume of the cone:

$V=\dfrac{1}{3}\pi r^2h$

2. Find the relation between the radius and the height:

r = diameter/2 = 5m/2 = 2.5m

h = 5.2m

h/r =5.2 / 2.5 = 2.08

3. Filling the tank:

Call y the height of water and x the horizontal distance from the axis of symmetry of the cone to the wall for the surface of water, when the cone is being filled.

The ratio x/y is the same r/h

x/y=r/h

y = x . h / r

The volume of water inside the cone is:

$V=\dfrac{1}{3}\pi x^2y$

$V=\dfrac{1}{3}\pi x^2(2.08)\cdot x\\\\\\V=\dfrac{2.08}{3}\pi x^3$

4. Find the derivative of the volume of water with respect to time:

$\dfrac{dV}{dt}=2.08\pi x^2\dfrac{dx}{dt}$

5. Find x² when the volume of water is 8π m³:

$V=\dfrac{2.08}{3}\pi x^3\\\\\\8\pi=\dfrac{2.08}{3}\pi x^3\\\\\\ 11.53846=x^3\\ \\ \\ x=2.25969\\ \\ \\ x^2=5.1062$ m²

6. Solve for dx/dt:

$1.2m^3/min=2.08\pi(5.1062m^2)\dfrac{dx}{dt}$

$\dfrac{dx}{dt}=0.03596m/min$

7. Find dh/dt:

From y/x = h/r = 2.08:

$y=2.08x\\\\\\\dfrac{dy}{dx}=2.08\dfrac{dx}{dt}\\\\\\\dfrac{dy}{dt}=2.08(0.035964m/min)=0.0748m/min\approx0.075m/min$

That is the rate at which the water level is rising when there is 8π m³ of water.

4 0

2 years ago

6=2(y+2) i need help

Snowcat [4.5K]

Answer:

y=1

Step-by-step explanation:

6=2(y+2)

6=2y+4

2=2y

y=1

3 0

2 years ago

Read 2 more answers

Two clocks are turned on at the same time. One clock chimes every 15 minutes. The

Kisachek [45]

Answer:

In 75 minutes, they will chime in together.

Step-by-step explanation:

First clock- 15, 30, 45, 60, 75

Second clock- 25, 50, 75

5 0

2 years ago

An FBI agent orders a block of ballistics gel. The gel weighs 54 pounds per cubic foot. What is the weight of the block of gel?

Pavlova-9 [17]

Answer:

It Should Be 32

Step-by-step explanation:

Because if you add the 20 6 and 6 it gives you 32 hope this helps

6 0

2 years ago

Read 2 more answers