Answer: Hypothesis testing
Step-by-step explanation:
In statistics , Hypothesis testing is a general procedure to check the results of a experiment or a survey to confirm that they have actual and valid results.
Given claim : A recent study claimed that half of all college students "drink to get drunk" at least once in a while. By believing that the true proportion is much lower, the College Alcohol Study interviews an SRS of 14,941 college students about their drinking habits and finds that 7,352 of them occasionally "drink to get drunk".
Here the College Alcohol Study is just testing the results of the survey .
Hence, this is is s a type of Hypothesis testing.
Answer: Downhill:10mph Uphill:5mph
Step-by-step explanation:
We are looking for Dennis’s downhill speed.
Let
r=
Dennis’s downhill speed.
His uphill speed is
5
miles per hour slower.
Let
r−5=
Dennis’s uphill speed.
Enter the rates into the chart. The distance is the same in both directions,
20
miles.
Since
D=rt
, we solve for
t
and get
t=
D
r
.
We divide the distance by the rate in each row and place the expression in the time column.
Rate
×
Time
=
Distance
Downhill
r
20
r
20
Uphill
r−5
20
r−5
20
Write a word sentence about the time.
The total time traveled was
6
hours.
Translate the sentence to get the equation.
20
r
+
20
r−5
=6
Solve.
20(r−5)+20(r)
40r−100
0
0
0
=
=
=
=
=
6(r)(r−5)
6
r
2
−30r
6
r
2
−70r+100
2(3
r
2
−35r+50)
2(3r−5)(r−10)
Use the Zero Product Property.
(r−10)=0
r=10
(3r−5)=0
r=
5
3
The solution
5
3
is unreasonable because
5
3
−5=−
10
3
and his uphill speed cannot be negative. So, Dennis's downhill speed is
10
mph and his uphill speed is
10−5=5
mph.
Check. Is
10
mph a reasonable speed for biking downhill? Yes.
Downhill:
10 mph
5 mph⋅
20 miles
5 mph
=20 miles
Uphill:
10−5=5 mph
(10−5) mph⋅
20 miles
10−5 mph
=20 miles
The total time traveled was
6
hours.
Dennis’ downhill speed was
10
mph and his uphill speed was
5
mph.
Answer:
A
Step-by-step explanation:
Answer:
The rearrangement can be 45, 987 , 310
Step-by-step explanation:
Here, we want to rearrange the number such that 9 is worth 10 times as what it is worth presently
The value of 9 presently is 90,000
So 10 times as worth will be 10 * 90,000 = 900,000
So we can have the new arrangement as;
45, 987, 310
Answer:
x=5±√−103/8
Step-by-step explanation:
There's no real solutions
4x2−3x+9−(2x+1)=2x+1−(2x+1)
4x2−5x+8=0
x=−b±√b2−4ac/2a
x=−(−5)±√(−5)2−4(4)(8)/2(4)
x=5±√−103/8
