Answer:
30 mph
Step-by-step explanation:
time = distance/speed
If x represents Jane's speed along the summit then her total exploration time is ...
12/x + 40/(x -5) = 2 . . . . . hours
Multiplying by (x)(x -5), we get ...
12(x -5) +40(x) = 2(x)(x -5)
Dividing by 2 and subtracting the left side gives ...
x^2 -31x +30 = 0
(x -30)(x -1) = 0 . . . . . factor
Solutions are x = 30 and x = 1, values of x that make the factors zero. A speed of 1 mph makes no sense in this problem, so ...
Jane's speed along the summit was 30 mph.
Answer:
Step-by-step explanation:
a) 20% decrease, b) 25% increase
Answer: 38 pages per night
Step-by-step explanation:
Tori used to read an average of 40 pages per night but now she is going at a rate that is 5% slower.
To find the number of pages she is reading now, first find 5% of 40 pages:
= 5% * 40
= 2
Then subtract this figure from 40:
= 40 - 2
= 38 pages per night
<em>By deducting 5% from the reading quantity, the person is reading at 5% less. </em>
Answer:
0.4 sec
Step-by-step explanation:
Remember that
1 mile=5,280 feet
1 foot=12 inches
1 hour=3,600 seconds
Let
s -----> the speed in ft/sec
d ----> the distance in ft
t -----> the time in sec
s=d/t
Solve for t
t=d/s
step 1
Convert miles/hour to ft/sec
105 mi/h=105(5,280/3,600)=154 ft/sec
Convert 60 ft 6 in to ft
60 ft 6 in=60+(6/12)=60.5 ft
step 2
Find the time
t=d/s
we have
s=154 ft/sec
d=60.5 ft
substitute
t=60.5/154
t=0.39 sec
Round to the nearest tenth
t=0.4 sec
Answer:
The solution is (0, 3)
Step-by-step explanation:
First, reduce 2x + 4y = 12 to x + 2y = 6, for easier calculations.
Next, substitute y - 3 for x in the other equation:
y - 3 + 2y = 6, or
3y = 9
Then y = 3. Since x = y - 3 in general, x = 3 - 3 = 0 when y = 3.
The solution is (0, 3)
