Question

Solve the problem by defining a variable and writing an equation

Answer 1

Randy and Wade started riding a bike at noon. Noon is 12 pm. Both of them are heading towards each other and 60km.

let

speed of wade = x

speed of Randy = 4 + x

They met each other at 1:30 pm. 12 pm to 1:30 pm is 1 hour 30 minutes(1.5 hours). Both of them will cover a total distance of 60km.

`\begin{gathered} \text{speed}=\frac{dis\tan ce}{\text{time}} \\ \text{speed}* time=dis\tan ce \end{gathered}`

Therefore,

`\begin{gathered} 1.5x+1.5(4+x)=60 \\ 1.5x+6+1.5x=60 \\ 3x=60-6 \\ 3x=54 \\ x=(54)/(3) \\ x=18\text{ km/hr} \end{gathered}`

speed of wade = 18km/hr

speed of Randy = 4 + 18 = 22km/hr