The formula for Average speed = 
The car travels 80 km in 1 hour.
Then the car travels 90 km in 2 hours.
And finally the car travels 76 km in 1 hour
So the total distance covered by the car = 80 + 90 + 76 = 246 km
The total time taken to cover this distance = 1 + 2 + 1 = 4 hours.
So average speed = 
The average speed of the car is 61.5 km / h
Answer:
420/69
Step-by-step explanation:
The angle of elevation of 61° and 72° with the height of the tower being 553.3 m. gives Vic's distance from Dan as approximately 356 meters.
<h3>How can the distance between Vic and Dan be calculated?</h3>
Location of Vic relative to the tower = South
Vic's sight angle of elevation to the top of the tower = 61°
Dan's location with respect to the tower = West
Dan's angle of elevation in order to see the top of the tower = 72°
Height of the tower = 553.3m



- Vic's distance from the tower ≈ 306.7 m
Similarly, we have;

- Dan's distance from the tower ≈ 179.8 m
Given that Vic and Dan are at right angles relative to the tower (Vic is on the south of the tower while Dan is at the west), by Pythagorean theorem, the distance between Vic and Dan <em>d </em>is found as follows;
- d = √(306.7² + 179.8²) ≈ 356
Therefore;
- Vic is approximately 356 meters from Dan
Learn more about Pythagorean theorem here:
brainly.com/question/343682
#SPJ1
4c + 5h = 650 and
5c + 6h = 800 where c are chefs, h are helpers
Start by finding an expression for c
4c + 5h = 650
4c = 650 -5h
c = (650- 5h)/4
Then substitute that into the second equation and solve for a number value for h
5 (650-5h)/4 + 6h = 800
(3250-25h)/4 + 6h = 800
Multiply both sides by 4
3250-25h + 24h = 3200
-h = -50
h = 50
Take that 50 and substitute it into the expression we have for c to get a number value for c
C= 650-5(50)/4
C = 650-250/4
C = 400/4
C= 100
Check your first equations, substituting $50 for the helpers and $100 for the chefs.
4 (100) + 5(50) =
400 + 250 = 650
5(100) + 6(50) =
500 + 300 = 800