What is the average speed for a car traveling at 90 km/h for the first 20 minutes and 60 km/h for the next 30 minutes?
Solutions:
1. Solve for the distance traveled in the first 20 minutes
= 90 km/h x 20 minutes
= 30 km
To solve this, we need to make sure that all units are consistent. So, in this case, we have hours and minutes. So, we need to convert to hour to make it consistent and the most common unit of speed is km/hr.
Equation:
Distance = Speed x Time
Solution:
Distance = \frac{90 km}{hr} x \frac{1 hr}{60 min} x 20 min
hr
90km
x
60min
1hr
x20min
Then, we will have
\frac{90 x 20}{60}
60
90x20
= 30 km
2. Solve for the distance traveled in the next 30 minutes
= 60 km/h x 30 minutes
= 30 km
We will be using the same formula.
Equation:
Distance = Speed x Time
Solution:
Distance = \frac{60 km}{hr} x \frac{1 hr}{60 min} x 30 min
hr
60km
x
60min
1hr
x30min
Then, we will have
\frac{60x30}{60}
60
60x30
= 30 km
3. What is the total distance? (Combine your answers in nos. 1&2)
= 30 km + 30 km
= 60 km
4-5. Solve for average speed.
Average speed = total distance ÷ total time =
= 72 km/h
Equation:
Average speed = total distance (answer from # 3) ÷ total time (20 min + 30 min)
Answers & Comments
Answer:
What is the average speed for a car traveling at 90 km/h for the first 20 minutes and 60 km/h for the next 30 minutes?
Solutions:
1. Solve for the distance traveled in the first 20 minutes
= 90 km/h x 20 minutes
= 30 km
To solve this, we need to make sure that all units are consistent. So, in this case, we have hours and minutes. So, we need to convert to hour to make it consistent and the most common unit of speed is km/hr.
Equation:
Distance = Speed x Time
Solution:
Distance = \frac{90 km}{hr} x \frac{1 hr}{60 min} x 20 min
hr
90km
x
60min
1hr
x20min
Then, we will have
\frac{90 x 20}{60}
60
90x20
= 30 km
2. Solve for the distance traveled in the next 30 minutes
= 60 km/h x 30 minutes
= 30 km
We will be using the same formula.
Equation:
Distance = Speed x Time
Solution:
Distance = \frac{60 km}{hr} x \frac{1 hr}{60 min} x 30 min
hr
60km
x
60min
1hr
x30min
Then, we will have
\frac{60x30}{60}
60
60x30
= 30 km
3. What is the total distance? (Combine your answers in nos. 1&2)
= 30 km + 30 km
= 60 km
4-5. Solve for average speed.
Average speed = total distance ÷ total time =
= 72 km/h
Equation:
Average speed = total distance (answer from # 3) ÷ total time (20 min + 30 min)
S = \frac{d}{t}S=
t
d
S = \frac{60 km}{50 min}S=
50min
60km
But we need to convert to hour, so:
S = \frac{60 km}{50 min} x \frac{60 min}{1 hr}S=
50min
60km
x
1hr
60min
Solution:
S = \frac{60 x 60}{50}S=
50
60x60
S = \frac{3600}{50}S=
50
3600
S = 72 km/h
Learn More:
1. Formula for Average Speed: brainly.ph/question/2591225
2. Example Problem for Average Speed: brainly.ph/question/9075394
3. What is Speed? brainly.ph/question/2149958