1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
trasher [3.6K]
3 years ago
14

Jane and sali cycled along the same 63 km route.

Mathematics
1 answer:
Alina [70]3 years ago
8 0

Answer:

<em>Sali's speed was 18.75 km/h.</em>

Step-by-step explanation:

Jane took 3.5 hours to cycle the 63 km.

As,  Speed= \frac{Distance}{Time} , so the speed of Jane will be:  \frac{63}{3.5} km/h = 18 km/h

Suppose, the speed of Sali is  x km/h

Sali caught up with Jane when they had both cycled 30 km.

So, <u>the time required for Jane to cycle 30 km</u> = \frac{30}{18}=\frac{5}{3} hours and <u>the time required for Sali to cycle 30 km</u>  =\frac{30}{x} hours

Given that, Sali started to cycle 4 minutes or (\frac{4}{60}) or (\frac{1}{15}) hours after Jane started to cycle. So, the equation will be.......

\frac{5}{3}-\frac{30}{x}= \frac{1}{15}\\ \\ \frac{30}{x}= \frac{5}{3}-\frac{1}{15}\\ \\ \frac{30}{x}= \frac{24}{15}\\ \\ 24x=450\\ \\ x= \frac{450}{24}= 18.75

Thus, the speed of Sali was 18.75 km/h.

You might be interested in
Can you help with these two questions?
Lady bird [3.3K]

1) 155.91 grams would be left after 10 years

2) The population would be 376,478 in 2040

Step-by-step explanation:

The form of the exponential function is y=a(b)^{x} , where

  • a is the initial amount (y at x = 0)
  • b is the growth/decay factor
  • b = 1 + r, where r is the rate of growth
  • b = 1 - r, where r is the rate of decay

1)

Scientists are studying a 500 grams sample of a radioactive element, which has an annual decay rate of 11%

∵ The initial amount is 500 grams

∴ a = 500

∵ The annual decay rate is 11%

∴ r = 11% = 11 ÷ 100 = 0.11

∵ b = 1 - r ⇒ decay

∴ b = 1 - 0.11 = 0.89

- We need to find how many grams of the sample would be left

  after 10 years

∴ x = 10

- Substitute all of these values in the form of the exponential function

∵ y=500(0.89)^{10}

∴ y = 155.9085996

- Round it to 2 decimal places

∴ y = 155.91

155.91 grams would be left after 10 years

2)

In 2000, the population of an Ohio town was 140,212. The population is expected to grow at a rate of 2.5% each year

∵ The population of an Ohio town was 140,212

∴ a = 140.212

∵ The population is expected to grow at a rate of 2.5% each year

∴ r = 2.5% = 2.5 ÷ 100 = 0.025

∵ b = 1 + r ⇒ growth

∴ b = 1 + 0.025 = 1.025

- We need to find the population in 2040

∵ The number of years is 2040 - 2000 = 40 years

∴ x = 40

- Substitute all of these values in the form of the exponential function

∵ y=140212(1.025)^{40}

∴ y = 376478.1709

- Round it to the nearest whole number

∴ y = 376,478

The population would be 376,478 in 2040

Learn more:

You can learn more about the functions in brainly.com/question/11921476

#LearnwithBrainly

6 0
3 years ago
The points <br> , 2r<br> and <br> , 104<br> lie on a line with slope <br> 54<br> .
Travka [436]
Dxpwkocpqwl,e-psol,;ce,s-plcwe'd,slpxos;w',]po
3 0
3 years ago
There are 23 classes in the fourth grade. Each grade has 21 students. Write a number sentence that will provide a reasonable est
lapo4ka [179]
23 can round to 20 and 21 can also round to 20 so all u do is 20x20=400 so 400 is your estimated answer
6 0
3 years ago
Somebody please help me
lara31 [8.8K]
-6 ≥ 10 - 8x        Subtract 10 from both sides
-16 ≥ -8x             Divide by -8 to both sides
x ≥ 2       your answer is c
5 0
3 years ago
Yati has a coin box containing some coins. 40% of the coins are 20-cent coins and the rest are 50-cent coins.
lana66690 [7]

The fraction that should be removed is 1/5.

<h3>How to calculate the fraction?</h3>

It should be noted that from the information, 40% of the coins are 20-cent coins and the rest are 50-cent coins. Those that are 50 cent will be:

= 100 - 40%

= 60%

The fraction that's should be removed will be:

= 2/5 - x = 1/5

x = 2/5 - 1/5

x = 1/5

The fraction that should be removed is 1/5.

Learn more about fractions on:

brainly.com/question/17220365

#SPJ1

7 0
1 year ago
Other questions:
  • Which relation is a function?
    11·2 answers
  • Beth bought 3 pairs of earrings for $4.50 each and 2 bracelets for $5.00 each. She gave the clerk $25.00. How much change did Be
    14·1 answer
  • What is the distance between (-6,8) and (-3,9)?
    7·2 answers
  • Larry's account has a balance of −$62.50. If he owes the bank more than $50, his account gets closed. Which of the following is
    8·2 answers
  • Attack on titan fans<br>What are your thoughts on s4 episode 1?<br><br><br><br><br><br><br>2+9​
    8·2 answers
  • Given circle o, what are the values of x and y?
    8·1 answer
  • One fifth of one number and one fourth of a number are added, the result is 29. What is the original number?
    13·1 answer
  • The graph of f(x) = 0.4x is replaced by the graph of g(x) = 0.4x + k. If g(x) is obtained by shifting f(x) up by 4 units, then w
    6·1 answer
  • Factorize: cos4θ + sin3θ . cosθ
    12·1 answer
  • What is the slope of the line that passes through the points (9, -5) and (1, -1)? Write your answer in simplest form.
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!