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2 years ago

Find the area of this semi-circle with diameter 18 Give your answer rounded to 2 DP.

Mathematics

1 answer:

ANTONII [103]2 years ago

5 0

Step-by-step explanation:

diameter(d): 18

radius(r): 18 ÷ 2 = 9

area of a semi-circle:

$\frac{\pi {r}^{2}}{2}$

$= \frac{\pi \times 9 \times 9}{2} = 127.23$

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When the turnpike littered the toll, traffic increased from 1,500 cars per day to 2,700

umka21 [38]

Answer:

80%

Step-by-step explanation:

The percentage change between two numbers can be calculated as ...

percentage change = ((new value)/(old value) -1) × 100%

= (2700/1500 -1) × 100% = (1.80 -1) × 100% = 80%

Traffic volume increased 80%.

6 0

3 years ago

A nutritionist planning a diet for a rugby player wants him to consume 3,650 Calories and 650 grams of food daily. Calories from

Tcecarenko [31]

Answer:

300

Step-by-step explanation:

because when multiply then divide all of them then find a percent 300 is your answer

8 0

3 years ago

Read 2 more answers

In the triangle below, 4/5 represents which ratio?

ASHA 777 [7]

Answer:
sin (C)

Explanation:
In a right-angled triangle, special trig functions can be applied. These functions are as follows:
sin (theta) = $\frac{opposite}{hypotenuse}$

cos (theta) = $\frac{adjacent}{hypotenuse}$

tan (theta) = $\frac{opposite}{adjacent}$ 

Now, let's check the triangle we have:
We have two options:
First option:
5 is the hypotenuse of the triangle
4 is the side adjacent to angle B
Therefore, we can apply the cos function:
cos (B) = $\frac{4}{5}$ 

Second option:
5 is the hypotenuse of the triangle
4 is the side opposite to angle C
Therefore, we can apply the sin function:
sin (C) = $\frac{4}{5}$

Among the two options, the second one is the one found in the choices. Therefore, it will be the correct one.

Hope this helps :)

8 0

3 years ago

Read 2 more answers

Find the average rate of change of the function over the given interval.

Minchanka [31]

Answer:

Average rate of change = 20.2

Rate of change at the left endpoint : f' (5) = 4t = 20

Rate of change at the right endpoint : f' (5.1) = 4*5.1 = 20.4

Step-by-step explanation:

The average rate of change of the function

F(t) = 2t^2 - 1 , [ 5,5.1 ]

solution

$\frac{f(5.1)-f(5)}{5.1 - 5}$ = $\frac{2*(5.1)^2-1-(2*5^2-1)}{0.1}$ = [ 2 ( 26.01 - 25 ) / 0.1 ]

= 2.02 / 0.1 = 20.2

Rate of change at the left endpoint : f' (5) = 4t = 20

Rate of change at the right endpoint : f' (5.1) = 4*5.1 = 20.4

6 0

3 years ago

A jet airplane, departing on time and flying between two airports at an average speed of $540 mph, arrives eight minutes late. D

Leokris [45]

<h3>Answer: 3240 miles</h3>

========================================

Work Shown:

Convert the given speeds from "miles per hour" to "miles per minute"

540 mi/hr = (540 mi/hr)*(1 hr/60 min)

540 mi/hr = (540/60) (mi/min)

540 mi/hr = 9 mi/min

480 mi/hr = (480 mi/hr)*(1 hr/60 min)

480 mi/hr = (480/60) (mi/min)

480 mi/hr = 8 mi/min

---------------

Let,

d = distance between two airports
x = time in minutes it takes the plane to travel 9 mi/min
y = time in minutes it takes the plane to travel 8 mi/min

If the plane travels 9 mi/min, then,

distance = rate*time

d = 9*x

d/9 = x

x = d/9

Similarly if the plane travels 8 mi/min, then,

d = 8*y

d/8 = y

y = d/8

Subtract the time values y and x

y-x = d/8 - d/9

y-x = 9d/72 - 8d/72

y-x = (9d-8d)/72

y-x = d/72

This difference represents 45 minutes because 53 - 8 = 45. The 53 and 8 are from the fact the plane is late 53 minutes and 8 minutes.

In other words, y-x = 45, so d/72 = 45 which solves to d = 3240 when you multiply both sides by 72.

---------------------------------

Extra Info:

If d = 3240, then

x = d/9 = 3240/9 = 360

y = d/8 = 3240/8 = 405

So y-x = 405 - 360 = 45

If the plane travels 9 mi/min (aka 540 mph) then it spends 360 minutes (6 hours) doing so. If the plane travels 8 mi/min (480 mph) then it spends 405 minutes (6 hrs, 45 min) doing so. So this is a more detailed look at why the time gap is 45 minutes.

4 0

3 years ago