1) In this problem, the first thing to do is to enlist the categories:
workers time to clean # apartments
8 2h15 12
8 9 x
2) Note that the number of cleaners is the same. So, we can pick the ratios that fall under the category <em>time </em>and <em>#apartments</em>
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We need to convert that 2h 15 into decimal form before setting the ratios:
3) Now, we can set the ratios and solve for x:
Thus, the answer is 48
Answer: the speed of the river is 9km/h
Step-by-step explanation:
Let x represent the speed of the river current.
He rides 140 km downstream in a river in the same time it takes to ride 35km upstream. This means that his speed was higher when riding downstream and it was lower when riding upstream.
Assuming he rode in the direction of the river current when coming downstream and rode against the current when going upstream.
time = distance/speed
Manuel has a boat that can move at a speed of 15 km/h
His downstream speed would be
15 + x
time spent coming downstream would be
140/(15 + x)
His downstream speed would be
15 - x
time spent going downstream would be
35/(15 - x)
Since the time is the same, then
140/(15 + x) = 35/(15 - x)
Crossmultiplying
140(15 - x) = 35(15 + x)
2100 - 140x = 525 + 35x
140x + 35x = 2100 - 525
175x = 1575
x = 1575/175
x = 9
Outliers should be excluded when producing a trend line, regardless of the method used.
The student got a score of 100 with no sleep.
This data pair was a rare event.
If the outlier was included, it would cause the trend line to misrepresent the typical data relationship.
The answer is the second one
