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If the time to climb the mountain took an hour more than the time to hike down how long was entire hike?

If the time to climb the mountain took an hour more than the time to hike down how-example-1

1 Answer

5 votes

4.8 mi

Step-by-step explanation


\text{time}=\text{ }\frac{\text{distance}}{\text{rate}}

Step 1

Set the equations

a) uphill

let

rate1= 1.5 miles per hour

time= unknow= t1

distance = x

b) down hille

rate=4 miles per hour

time=time2=one hour less than the time to climb = t1-1

distance = x

so

replacing


\begin{gathered} t_1=\frac{x}{1.5\frac{mi}{\text{hour}}}\rightarrow t_1=(x)/(1.5)\rightarrow equation(1) \\ t_2=\frac{x}{4\frac{mi}{\text{hour}}} \\ \text{replace t}_2=t_1-1 \\ t_1-1=(x)/(4) \\ \text{add 1 in both sides} \\ t_1-1+1=(x)/(4)+1 \\ t_1=(x)/(4)+1\rightarrow equation(2) \end{gathered}

Step 2

solve the equations


\begin{gathered} t_1=(x)/(1.5)\rightarrow equation(1) \\ t_1=(x)/(4)+1\rightarrow equation(2) \end{gathered}

set t1= t1


\begin{gathered} t_1=t_1 \\ (x)/(1.5)=(x)/(4)+1 \\ (x)/(1.5)=(x+4)/(4) \\ 4x=(x+4)1.5 \\ 4x=1.5x+6 \\ subtract\text{ 1.5 x in both sides} \\ 4x-1.5x=1.5x+6-1.5x \\ 2.5x=6 \\ \text{divide both sides by 2.5} \\ (2.5x)/(2.5)=(6)/(2.5) \\ x=2.4 \end{gathered}

it means the distance to the top of the mountain is 2.4 miles, so the entire hike is twice that amount

total distance=2.4 mi*2

total distance=4.8 miles

Step 3

now, the times


\begin{gathered} t_1=(x)/(1.5) \\ t_1=(2.4)/(1.5) \\ t_1=1.6\text{ hours} \\ t_2=t_1-1 \\ t_2=1.6-1=\text{ 0.6 hours} \end{gathered}

table

I hope this helps you

If the time to climb the mountain took an hour more than the time to hike down how-example-1
User Ralph Bergmann
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