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3 years ago

10

Explain why you can use πr2 to find the area of the base of a cone

1 answer:

olga nikolaevna [1]3 years ago

8 0

The base of a cone is a circle.

The area of a circle is $\pi r^2$ .

Thus, the area of the base of a cone $\pi r^2$ .

The derivation of the formula for the area of a circle involves a bit of calculus, but if you'd like, I can walk you through it.

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What is the likelihood that the children in square 2 will have earlobes that are not attached?

notka56 [123]

Answer : 2/4 children will have earlobes that are not attached

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3 years ago

What’s a complex conjugate in math

goldenfox [79]

Answer:

Step-by-step explanation:

In mathematics, the complex conjugate of a complex number is the number with an equal real part and an imaginary part equal in magnitude but opposite in sign. For example, the complex conjugate of 3 + 4i is 3 − 4i. In polar form, the conjugate of is.

3 0

3 years ago

On his outward journey, Ali travelled at a speed of s km/h for 2.5 hours. On his return journey, he increased his speed by 4 km/

den301095 [7]

Answer:

3.08 km/h.

Step-by-step explanation:

We know that,

$Speed=\dfrac{Distance}{Time}$

Ali traveled at a speed of s km/h for 2.5 hours.

Let d be the distance and t be the time.

$2.5=\dfrac{d}{t}$

$2.5t=d$ ...(1)

On his return journey, he increased his speed by 4 km/h and saved 15 minutes. So, distance is d and times is t-15.

$4=\dfrac{d}{t-15}$

$4(t-15)=d$ ...(2)

From (1) and (2), we get

$4(t-15)=2.5t$

$4t-60-2.5t=0$

$1.5t=60$

$t=40$

Put t=40 in (1).

$d=2.5(40)=100$

So, t=40 and d=100.

Now,

Total distance = d + d = 100 + 100 = 200

Total time = t + t - 15 = 40 + 40 - 15 = 65

So, the average speed is

$\text{Average speed}=\dfrac{\text{Total distance}}{\text{Total time}}$

$\text{Average speed}=\dfrac{200}{65}$

$\text{Average speed}\approx 3.08$

Therefore, the average speed is 3.08 km/h.

3 0

4 years ago

All of the expressions that have the same value as LaTeX: 892\div8892 ÷ 8. Group of answer choices LaTeX: 8920\div808920 ÷ 80 La

algol13

Answer:

$(a)$ $8920\div80$

$(e)$ $0.892\div0.008$

Step-by-step explanation:

Given

$892\div8$

Required

Select equivalent expression

$8920\div80$

$894\div10$

$89.2\div0.08$

$8.92\div0.8$

$0.892\div0.008$

Start by solving the given expression (using a calculator)

$892\div8$ $= 111.5$

Then we solve the given options (using a calculator)

$(a)$ $8920\div80$

$8920\div80$ $= 111.5$

$(b)$ $894\div10$

$894\div10$ $= 89.4$

$(c)$ $89.2\div0.08$

$89.2\div0.08$ $= 1115$

$(d)$ $8.92\div0.8$

$8.92\div0.8$ $= 11.15$

$(e)$ $0.892\div0.008$

$0.892\div0.008$ $= 111.5$

The equivalent expressions are (a) and (e)

5 0

3 years ago

Marie is making a recipe that calls for 1 cups of oil. How many fluid ounces of oil should she use?

dybincka [34]

1 cup of oil would equal up to 8 fluid ounces

7 0

3 years ago

Read 2 more answers