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Two buses leave a station at the same time and travel in opposite directions. One bus travels 9 mi h slower than the other. If the two buses are 585 miles apart after 5 hours, what is the rate of each bus?

Respuesta :

Answer:

The speed of the buses are 58.2 mph and 49.2 mph.

Step-by-step explanation:

Let the speed of bus 1 is x mph.

So, the other bus 2 has speed (x - 9) mph.

Then time-traveled to cover 585 miles by bus 1 will be [tex]\frac{585}{x}[/tex] hours.

Again time-traveled to cover 585 miles by bus 2 will be [tex]\frac{585}{x - 9}[/tex] hours.

Therefore, from the condition given  

[tex]\frac{585}{x - 9} - \frac{585}{x} = 9[/tex]

⇒ [tex]65(\frac{1}{x-9} -\frac{1}{x}) = 1[/tex]

⇒ [tex]x^{2} - 9x - 585 = 0[/tex]

Applying the Sridhar Acharya formula

[tex]x = \frac{9+\sqrt{9^{2}- 4 \times (-585) } }{2}[/tex] {Neglecting the negative root}

x = 58.2 mph

So, x - 9 = 49.2 mph

Therefore, the speed of the buses are 58.2 mph and 49.2 mph. (Answer)

Answer:

The speed of bus 1 is 63 mile per hour  And bus 2 is 54 mile per hour  

Step-by-step explanation:

According to question

Let the speed of bus 1 = [tex]S_1[/tex] = S  mph

and The sped of bus 2 =  [tex]S_2[/tex]  = S - 9  mph

Let The distance travel by bus 1 =  [tex]D_1[/tex] = D mile

And The distance travel by bus 2 =  [tex]D_2[/tex]  = ( 585 - D ) mile

he time taken by both buses to cover distance = T hour

Now, Distance = Speed × Time

So ,    [tex]D_1[/tex] =  [tex]S_1[/tex] × T

Or,                         D = S × T                         ......... 1

Again  [tex]D_2[/tex] =  [tex]S_2[/tex] × T

Or,            ( 585 - D ) = (  S - 9 ) × T            ..........2

From eq 1 an eq 2

       585 - S ×T  = S ×T - 9 T

Or,   585 + 9 T = 2 × S ×T

Or,   585 + 9 × 5 = 2 × S × 5

Or,   585 + 45  = 10 × S

So , 630 = 10 × S

∴          S = [tex]\frac{630}{10}[/tex] = 63  mph

And     S -9 = 63 - 9 = 54  mph

Hence The speed of bus 1 is 63 mile per hour  And bus 2 is 54 mile per hour   Answer