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:
50
Step-by-step explanation:
From research among high school students in the US, it was discovered in 2017 by US Centre for Disease Control and Prevention Agency(USCDC), that around 57.8% of high school students have drank alcohol in the previous 1 year.
Now, applying it to this question, since the survey is done among 100 seniors, the most modest probability would likely be 50% which represents 50 people out of the 100 surveyed that will likely check yes
17 times 4, you get 68. 68 minus 35, your answer is 33
17*4=68
68-35=33
Answer:
LN = 66 cm
Step-by-step explanation:
The 3 parallel lines divide the 2 sides they intersect in proportion, that is
= 
, substitute values
= 
( cross- multiply )
15LM = 315 ( divide both sides by 15 )
LM = 21
Hence
LN = LM + MN = 21 + 45 = 66 cm
Answer:
a) P) 0.25 = 1/4 both
b) P) 0.75 = 3/4 one
c) P) 0.25 = 1/4 none
Step-by-step explanation:
4 routes to D + H
6 routes to H + S
= D H S
4 | 6
- 2 | -3
= 2 | 3 = route 1 = 2/4 and route 2 = 3/6
= 1/2 route 1 and 1/2 route 2
Answer a ) = 1/2 x 1/2 = 0.25 = 1/4 = 0.25 probability
Answer b) = 1- (1/2 x 1/2) = 1- 0.25 = 3/4 = 0.75 probability
Answer c) = 1/2 x 1/2 = 0.25 = 1/4 = 0.25 probability
