Question

A fast Humvee drove from Desert A to Desert B. for the first 12 hours and traveled at an average speed of 185 km/h. For the next 13 hours, it travelled at an average speed of 160 km/h. What was the average speed of the whole journey?

Answer 1

The value is
`v_t = 172 \ km/h`

Step-by-step explanation:

From the question we are told that

The average speed for the first 12 hours is
`u = 185 km/h`

The average speed for the next 13 hours is
`v = 160 \ km/h`

Generally the total time taken is mathematically represented as

`t_t = 12 + 13`

=>
`t_t = 25 \ h`

The distance covered in the first movement is

`D = u * 12`

`D = 185 * 12`

`D = 2220 \ km`

The distance covered in the first movement is

`d= v * 13`

`d = 160 * 13`

`d = 2080 \ km`

The total distance traveled is

`D_t = D + d`

`D_t = 2220 +2080`

`D_t = 4300 \ km`

The average of the whole journey is

`v_t = (D_t)/(t_t)`

`v_t = (4300)/(25)`

`v_t = (4300)/(25)`

`v_t = 172 \ km/h`