Answer:
C. 
Step-by-step explanation:
To find the number of black ribbons one would have subtract the amount of red ribbons from the total number of ribbons. Then one would have to express it as a proportion. Part over whole equals percent over 100. The number of black ribbons over total ribbons equals "b" over 100.
Answer:
Step-by-step explanation:
Craig left his house at noon and drove 50 miles per hour until 3PM. Then he drove the next 5 hours at 70 miles per hour. Calculate the average rate of change for the entire trip.
The answer is b. 2,8 and 3,11
8=3(2)+2
8=6+2
8=8
11=3(3)+2
11=9+2
11=11
To solve this problem, we must recall that the formula
for velocity assuming linear motion:
v = d / t
Where,
v = velocity
d = distance
t = time
For condition 1: bus travelling on a level road
v1 = d1 / t1
<span>(v2 + 20) = (449 – d2) / 4 --->1</span>
For condition 2: bus travelling on a winding road
v2 = d2 / t2
<span>v2 = d2 / 5 --->2</span>
Combining equations 1 and 2:
(d2 / 5) + 20 = (449 – d2) / 4
0.8 d2 + 80 = 449 – d2
1.8 d2 = 369
d2 = 205 miles
Using equation 2, find for v2:
v2 = 205 / 5
v2 = 41 mph
Since v1 = v2 + 20
v1 = 41 + 20
v1 = 61 mph
Therefore
<span>the
average speed on the level road is 61 mph.</span>