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At noon Joyce drove to the lake at 30 miles per hour. but she made the long walk back home at 4 miles per hour. How long did she walk if she was gone for 17 hours? How far did she walk?

PLEASE GIVE A REAL ANSWER , WILL GIVE BRANILIEST

Respuesta :

semsee45

Answer:

60 miles

Step-by-step explanation:

let d = distance to the lake

Using:  time = distance ÷ speed

Create expressions for the time it takes for each journey:

Drive:  [tex]t_1=\dfrac{d}{30}[/tex]

Walk:   [tex]t_2=\dfrac{d}{4}[/tex]

If total time = 17 hours

[tex]\implies t_1+t_2=17[/tex]

[tex]\implies \dfrac{d}{30}+\dfrac{d}{4}=17[/tex]

[tex]\implies \dfrac{17d}{60}=17[/tex]

[tex]\implies 17d=1020[/tex]

[tex]\implies d=\dfrac{1020}{17}[/tex]

[tex]\implies d=60[/tex]

Therefore she walked 60 miles

Distance be x

  • Time=Distance/Speef

So

  • T_1=x/30
  • T_2=x/4

ATQ

[tex]\\ \tt\hookrightarrow T_1+T_2=17[/tex]

[tex]\\ \tt\hookrightarrow x/30+x/4=17[/tex]

[tex]\\ \tt\hookrightarrow 2x+15x/60=17[/tex]

[tex]\\ \tt\hookrightarrow 17x=1020[/tex]

[tex]\\ \tt\hookrightarrow x=60mi[/tex]

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