What is the value of R? (Assume R > 0) R/4=36/R A)8 B)9 C)12 D) 20

Louisa ran at an average speed of five miles per hour along an entire circular park path. Calvin ran along the same path in the

docker41 [41]

Answer:

15 miles

Step-by-step explanation:

Let $x$ be the miles in the circular park path, $t_{L}$ the time Louisa takes to finish and $t_{C}$ the time Calvin takes to finish both in hours.

Then $x$ , the longitude is equal to the velocity times the time used to finish. So

$x=5t_{L}$

$x=6t_{C}$

And the difference between Louisa's time and Calvin' time is 30 minutes, half an hour. So:

$t_{C}=t_{L}-0.5$

Three equations, three unknowns, the system can be solved.

Equalizing the equation with x :

$5t_{L}=6t_{C}$

In this last equation replace $t_{C}$ with the other equation and solve:

$5t_{L}=6(t_{L}-0.5)\\ 5t_{L}=6t_{L}-3\\ 3=6t_{L}-5t_{L}\\ 3=t_{L}\\ t_{L}=3$

With Louisa's time find x:

$x=5t_{L}\\ x=5(3)\\ x=15$

7 0

2 years ago

Given an arithmetic sequence with a3=5 and a5=19, find the 24th term.

krok68 [10]

The 24th term is 152

Step-by-step explanation:

The formula of the nth term of an arithmetic sequence is:

$a_n=a+(n-1)d$ , where

a is the first term
d is the common difference between consecutive terms

The third term means n = 3

∵ $a_3=a+(3-1)d$

∴ $a_3=a+2d$

∵ $a_3$ = 5

- Equate the right hand sides of the third term

∴ a + 2d = 5 ⇒ (1)

The fifth term means n = 5

∵ $a_5=a+(5-1)d$

∴ $a_5=a+4d$

∵ $a_5$ = 19

- Equate the right hand sides of the fifth term

∴ a + 4d = 19 ⇒ (2)

Now we have a system of equations to solve it

Subtract equation (1) from equation (2) to eliminate a

∴ 2d = 14

- Divide both sides by 2

∴ d = 7

- Substitute the value of d in equation (1) to find a

∵ a + 2(7) = 5

∴ a + 14 = 5

- Subtract 14 from both sides

∴ a = -9

The twenty fourth term means n = 24

∵ a = -9 and d = 7

- Substitute the values of a and d in the formula of the nth term

∴ $a_24=-9+(24-1)(7)$

∴ $a_24=-9+(23)(7)$

∴ $a_24=-9+161$

∴ $a_24=152$

The 24th term is 152

Learn more:

You can learn more about the arithmetic sequence in brainly.com/question/7221312

#LearnwithBrainly

5 0

3 years ago

Find the solution set for the inequality x-10<10

Lelu [443]

Answer:

x<20

Step-by-step explanation:

x-10<10

add 10 to both sides

x<20

X can therefore be anything less than 20.

4 0

2 years ago

What property for each step?

PolarNik [594]

For the first one it’s subtraction property of equality

6 0

3 years ago

Read 2 more answers

Erica can paint her room 5 hours .If she had her friend Rachel help her , they can paint the room together in 3 hours .How long

LUCKY_DIMON [66]

Answer:

7 hours 30min

Step-by-step explanation:

Step one :

Given data

We are told that Erica can paint 1 room in 5hours

Her work rate is 1/5 room per hour

And also with the assistance of her friend they can paint 1 room in 3 hours

Hence their combined work rate is 1/3 room per hour

Step two

The combined work expression is

1/A+1/B=1/T

Where A=Erica's work rate

B=Rachael's work rate

T=combined work

1/5+1/B=1/3

1/B=1/3-1/5

1/B=5-3/15

1/B=2/15

B=15/2

B=7.5 hours

It will take Rachel 7 hours 30min to paint the room

4 0

3 years ago