Speed of the plane: 250 mph
Speed of the wind: 50 mph
Explanation:
Let p = the speed of the plane
and w = the speed of the wind
It takes the plane 3 hours to go 600 miles when against the headwind and 2 hours to go 600 miles with the headwind. So we set up a system of equations.
600
m
i
3
h
r
=
p
−
w
600
m
i
2
h
r
=
p
+
w
Solving for the left sides we get:
200mph = p - w
300mph = p + w
Now solve for one variable in either equation. I'll solve for x in the first equation:
200mph = p - w
Add w to both sides:
p = 200mph + w
Now we can substitute the x that we found in the first equation into the second equation so we can solve for w:
300mph = (200mph + w) + w
Combine like terms:
300mph = 200mph + 2w
Subtract 200mph on both sides:
100mph = 2w
Divide by 2:
50mph = w
So the speed of the wind is 50mph.
Now plug the value we just found back in to either equation to find the speed of the plane, I'll plug it into the first equation:
200mph = p - 50mph
Add 50mph on both sides:
250mph = p
So the speed of the plane in still air is 250mph.
Answers:
1. 1/4
2. 12:10
3. 3/23 in fraction form, or 0.13 in decimal form (though please note that the decimal form has been rounded to the nearest hundredth).
Explanations:
1. In order to simplify a fraction, you need to find a number that both the numerator and denominator can be divided by evenly. Once you cannot find any number that fits that description, you have found the simplest form. Both numbers 10 and 40 can be divided by the number 10 - so let's divide 10 by 10 and 40 by 10. After doing that, your answer should be 1/4.
2. In order to find an equivalent ratio of an existing ratio, you can just multiply or divide the numbers of that ratio by a same number. Knowing this, this question can have many correct answers, but in this case, I used the number 2, and multiplied both 6 and 5 by it. This left me with an equivalent ratio of 12:10.
3. In order to calculate probability, you need to divide the number of "winners" (or the outcome we want to have) by the number of all possible outcomes you could have. For this problem, that "winner" is the number of green shirts, which is 3. The number of outcomes would be the number of all the shirts in total, which adds up to 23. Thus, using that method explained earlier, the probability would be 3/23 in fraction form or 0.13 in decimal form (note that this is rounded to the nearest hundredth since dividing 3 by 23 would result in a long answer).
If he got all three today, he will get all 3 newsletters in the next 40days
<h3>Least common multiple</h3>
- Sports = every 5 days
- Model rail roads = every 10 days
- Music = every 8 days
Find the least common multiple of 5, 10 and 8
- 5 = 10, 15, 20, 25, 30, 35, 40, 45, 50
- 10 = 20, 30, 40, 50, 60
- 8 = 16, 24, 32, 40, 48, 56
The least common multiple of 5, 10 and 8 is 40
Therefore, If he got all three today, he will get all 3 newsletters in the next 40days
Learn more about least common multiple:
brainly.com/question/10749076
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Answer:
b
Step-by-step explanation:
