how do you solve these maths problems? someone explain to me??

Question

1. The driver of a car travelling at 60 km/h is 80 km behind the driver of another car travelling at 50 km/h. How long will it take the faster car to catch up with the slower car?

2. Find the volume of water in a cylindrical tank of diameter 1.4 m and height 60 cm. This water is poured into a rectangular trough of length 1.2 m and width 80 cm. Find the height of water in the trough. ( Take π = 22/7 )

Answer 1

How about trying it 1st before we give you the answer.

You won't learn and when it's your time to answer a question like that here, you're stuck.

Write down your steps so that everyone can see. Come on, give it a shot! There's no need to be ashame if you get it wrong.

Answer 2

The second car gains on the first by 10 km per hour, which is the difference in their speeds. So, it will take 8 hours to make up the 80 kms between them.

Part 2
To find the area, use 2 (pi r). Then multiply by the height to find the volume.

Answer 3

1. Assume time to overtake = t hours
In this time, the faster car drove 60*t kms
The slower car drove 50*t kms
To overtake the slower car, the faster can drove 80 kms more t han the slower car
Hence 50*t + 80 = 60*t => 10*t = 80 => t = 8 hrs

2. Volume of water in tank = area of cross section * height
= π * radius^2 = π*(diameter/2)^2 = 22/7 * 0.7 * 0.7 = 1.54 cubic meter
When the water is poured into a rectangualr trough, the height of water = (volume of water)/(area of cross section of trough)
Now area of cross section of trough = length * width = 1.2 * 0.8 = 0.96 square-meter
Hence height of water = 1.54/0.96 = 1.6042 m (approx)

Answer 4

1. 8 hours (Its a 10km/h diff. between 60 and 50km/h. The traveler of 60 is gaining 10km every hour so if travler 60 is behind traveler 50 by 80 km, divide 80 by 10 to get 8 because you gain ten every hour to reach 80km in which would make it 8 hours.)

2.? Need the formula: volume of a cylinder, cant remember

Answer 5

1.Q
60-50=10 km/h(The faster approaces the slower 10 kms per hour.) So, 80/10= 8 hours later they will be together.

2.Q is realy hard for me.

Answer 6

1.) 60X = 50X + 80

60x-50x = 80

10x = 80

x =8 hours

Not sure about the second one though. Sorry

Answer 7

I graduated from high school 28 years ago. I gotta tell ya, I don't need to know how to answer those questions. Why do they waste your time teaching you that stuff, rather than how to contribute to the world, and/or be happier?

Why not in class, just stand up and say out loud, "Why do we need to learn this stuff?"