Answer: 81.85 km/hr
Converting m/sec into km/hr, 25 m/sec = 90 km/hr
Average =
Time = 50/90 = 5/9 hr
next 120 km at an average speed of 80km/h
=> Time = 120/80 = 3/2 hr
last part of its journey at an average speed of 90km/h in 35 Minutes
time = 35 minutes = 35/60 hr = 7/12 hr
Distance covered = 90 * 7 /12 = 105/2 km
Total Distance = 50 + 120 + 105/2 = 435/2 km
Total time = 5/9 + 3/2 + 7/12 = ( 20 + 54 + 21) /36 = 95/36
Average speed = (435/2)/(95 /36) = 432 * 18 /95 = 81.85 km/hr
Answer:
B. (12-6) n - 50
Step-by-step explanation:
Given that:
Cost of making hat = $6 per hat
Selling price = $12 per hat
Advert cost = $50
Number of hats made = n
The profit or money raised from the sales of hat:
Total Revenue from sales - total cost of production - advert cost
Total Revenue from sales = ($12 * n) = $12n
Total cost of production = ($6 * n) = $6n
Advert cost = $50
Hence,
12n - (6n + 50)
12n - 6n - 50
(12 - 6)n - 50
Your two equations are at the top, in the box is what each variable represents. Below the box is total liters of the 15%, which is going to equal the total liters for 10% plus the total liters for 25%. Make your percentages into decimals. There’s a total of 30 liters so, x+y needs to equal 30. Isolate a variable, I chose y, you can do either or (isolating x would be more math). Y is going to equal 30-x, substitute that for the Y in the second equation, then you need to distribute 0.25 into 30-x. Then it’s simple math, subtract 7.50 from both sides, add like gets, divide both sides by -0.15, making x=20.
