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
Novosadov [1.4K]
3 years ago
10

Stoplight a changes color every 30 seconds and stoplight b changes every 40 seconds. after how many seconds will the stoplights

change colors at the same time again?
Mathematics
1 answer:
andrey2020 [161]3 years ago
6 0

Answer:

After 120 seconds

Step-by-step explanation:

Here, we want to know the number of seconds after which both spotlights will change colors at the same time again.

Basically, what we want to do here is to

calculate the value with which 30 and 40 have the same multiples or we want to

calculate the lowest common multiple of 30 and 40

The multiples of 30 are 30,60,90,120 etc

The multiples of 40 are 40,80,120 etc

We can see that the lowest common multiple of both is 120

So therefore the spotlights will change colors at the same time after 120 seconds

You might be interested in
When Theresa walks at a pace of 88 steps per minute, it takes her 90 minutes to walk the trail. If she alters her pace to 33 ste
jarptica [38.1K]

Answer: 33 minutes

Step-by-step explanation:

Hi to answer this question we have to write a proportion

Speed rate = 88 step per minute

Time = 90 minutes

So, the proportion is 88 step/min / 90 minutes

For 33 steps per minutes = 33 / x minutes

88/90 = 33/x

solving for x:

x= 33/ (88/90)

x = 33.75 = 33 minutes.

Feel free to ask for more if needed or if you did not understand something.

5 0
3 years ago
Calculate the surface area of the aquarium, without the top.<br>24 cm<br>80 cm<br>16 cm​
larisa86 [58]
Well you never sent a picture but the most logical answer is 80 cm
3 0
3 years ago
WANT POINTS JUST ANSWER THIS CORRECTLY FOR 45!!!
Lelu [443]
Since we’re trying to find minutes, concert all known information to minutes

1 hr 15 mins = 75 mins
1 hr 30 mins = 90 mins

Next, calculate how many total minutes Gage has skated in the first 8 days

75(5) + 90(3) = 645 mins

Create an equation to find the average of Gage’s minutes of skating. Add up all the minutes and divide by the total amount of days and set equal to 85, the average we are trying to get.

(645 mins + x mins)/9 days = 85

Solve for x

645 + x = 765
x = 120

So, in order to have an average of an 85 minute skate time, Gage would need to skate 120 minutes on the ninth day.
3 0
3 years ago
Help i need help with this question
makvit [3.9K]
The answer is the √26 and -√26. Look at the picture for explanation.

3 0
3 years ago
PLEASE HELP‼️‼️Drag the expression that is the most reasonable measurement for each object.
Afina-wow [57]

Answer:

<em>A. Length of a Tour Bus                       ↔     #2.      1.1 × 10¹ meters</em>

<em />

<em>B. Width of an apple                             ↔      #3.     4 × 10⁰ centimeters</em>

<em />

<em>C. Distance from Earth to a Satellite    ↔    #6.     8 × 10² kilometers</em>

<em />

<em>D. Thickness of a human hair               ↔     #5.      9 × 10¹ micrometers</em>

Explanation:

<u><em>A. Length of a tour bus.</em></u>

The length of a tour bus should be measured in meters. It sure is way less than 1 kilometer and way more than a few centimeters. It could be about some meters, more than 5 meters, may be between 10 meters and 15 meters.

The measurement in the box # 2. is 1.1 × 10¹ meters, which is equivalent to 1.1 × 10meters = 11 meters. Thus, this is a reasonable length.

<u><em>B. Width of an apple.</em></u>

The most appropiate unit to measure the width of an apple should be centimer. It certanly is shorter than 1 meter and bigger than 1 mm.

The width of an apple could be, more or less, around 8 centimeters. The only measurement in the boxes that is in that order is that in the box #3., 4 × 10⁰ centimeters, because 10⁰ = 1, so 4 × 10⁰ = 4 × 1 = 4centimeters.

<u><em>C. Distance from Earth to a Satellite</em></u>

The distance from Earth to a satellite should be measured in kilometers.

You can find in the internet that the distances of the satellites are between 700 kilometers and 36,000 kilometers.

The number in the box #1 is too big, in the order of ten trillions of kilometers, because one trillion is 10¹²; thus that is notreasonalbe (too big).

The number in the box #6 is  8 × 10² kilometers, which is equal to 8 × 100 = 800 kilometers.

Thus,  8 × 10² kilometers (box #6) is the most reasonable measurement for the distance from Earth to a Satellite

<u><em></em></u>

<u><em>D. Thickness of a human hair</em></u>

Of course, kilometers, meters, centimeters and even milimeters are units too big to measure the thickness of a human hair.

One micrometer is 10⁻⁶ meters or 10⁻³ milimeters.

In the internet you can find that diameter of the humar hairis in the range from 17 micrometers to 181 micrometers.

The measurement in the box #5. is 9 × 10¹ micrometers, which is equivalent to 9 × 10 = 90 micrometers.

Thus, 9 × 10¹ micrometers is the most reasonable measurement fot the thickness of a human hair.

7 0
3 years ago
Other questions:
  • Sketch one cycle of the cosine function y= cos 2θ
    13·1 answer
  • Population has a mean of 180 and a standard deviation of 24. a sample of 64 observations will be taken. the probability that the
    9·1 answer
  • 8 out of 40 men wear glasses. write this as a fraction in its lowest terms
    7·1 answer
  • If the function f is defined by f(x)=3x+4, then 2f (x) +4=
    9·1 answer
  • PLZ HURRY IT'S URGENT!!!!
    13·2 answers
  • Tara watched a movie at 3:19. The movie she watched was 1:20 long. When was her movie over?
    14·2 answers
  • Kim performed a transformation on rectangle ABCD to create rectangle A'B'C'D', as shown in the figure below:
    15·2 answers
  • Graph the linear equation 7x+4y=-28
    13·1 answer
  • If a load of snow contains 3 tons it will weigh how many pounds
    10·1 answer
  • Billie participated in a weight loss challenge at her work. She weighed 185 lbs in March and when the competition finished in Ma
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!