Question

On the first day of travel, a driver was going at a speed of 40 mph. The next day, he increased the speed to 60 mph. If he drove 2 more hours on the first day and traveled 20 more miles, find the total distance traveled in the two days.

Answer 1

Velocity, distance and time:

This question is solved using the following formula:

$v = \frac{d}{t}$

In which v is the velocity, d is the distance, and t is the time.

On the first day of travel, a driver was going at a speed of 40 mph.

Time $t_1$, distance of $d_1$, v = 40. So

$v = \frac{d}{t}$

$40 = \frac{d_1}{t_1}$

The next day, he increased the speed to 60 mph. If he drove 2 more hours on the first day and traveled 20 more miles

On the second day, the velocity is $v = 60$.

On the first day, he drove 2 more hours, which means that for the second day, the time is: $t_1 - 2$

On the first day, he traveled 20 more miles, which means that for the second day, the distance is: $d_1 - 20$

Thus

$v = \frac{d}{t}$

$60 = \frac{d_1 - 20}{t_1 - 2}$

System of equations:

Now, from the two equations, a system of equations can be built. So

$40 = \frac{d_1}{t_1}$

$60 = \frac{d_1 - 20}{t_1 - 2}$

Find the total distance traveled in the two days:

We solve the system of equation for $d_1$, which gets the distance on the first day. The distance on the second day is $d_2 = d_1 - 20$, and the total distance is:

$T = d_1 + d_2 = d_1 + d_1 - 20 = 2d_1 - 20$

From the first equation:

$d_1 = 40t_1$

$t_1 = \frac{d_1}{40}$

Replacing in the second equation:

$60 = \frac{d_1 - 20}{t_1 - 2}$

$d_1 - 20 = 60t_1 - 120$

$d_1 - 20 = 60\frac{d_1}{40} - 120$

$d_1 = \frac{3d_1}{2} - 100$

$d_1 - \frac{3d_1}{2} = -100$

$-\frac{d_1}{2} = -100$

$\frac{d_1}{2} = 100$

$d_1 = 200$

Thus, the total distance is:

$T = 2d_1 - 20 = 2(200) - 20 = 400 - 20 = 380$

The total distance traveled in two days was of 380 miles.

For the relation between velocity, distance and time, you can take a look here: https://brainly.com/question/14307500

Answer 2

Answer:

Total traveled distance is : 380 miles

Step-by-step explanation:

Let´s call variables of the first day of travel as:

v₁ = 40 mph

Time of travel  unknown but 2 hours more than the second day

Traveled distance ( unknown) but 20 miles more than the second day

And for the second day

v₂ = 60 mph

Time of travel t

Traveled distance s (unknown)

With that information, we can make a model of a two equations system as follows:

We know that s = v*t ( where s is the distance traveled, v the speed, and t the traveled time) then

First day  

Total distance traveled s + 20 is equal to:

s + 20 = 40 * ( t + 2 )

The second day:

s = 60*t

The system is:

s + 20 = 40 * ( t + 2 )

s = 60*t

By substitution

60*t + 20 = 40 * ( t + 2 )

60*t + 20 = 40*t + 80

60*t - 40*t = 80 - 20

20*t = 60

t = 3 hours

Now we can calculate the total distance traveled according to:

First day:  s₁ = 40 (m/h)* (t + 2) (h) = 40*5 miles      s₁ = 200 miles

Second day:

s = 60*t   =  60 (m/h)*3 (h)  =  180 miles

Total distance is : 380 miles