Chapter 6.5, Problem 45STP

To determine

To calculate: The duration of a person who will be in line that moves 30 feet with the rate 5 feet per 20 minutes.

Answer to Problem 45STP

It takes 120 minutes or 2 hours by a person, to move 30 feet in the line. Or, option J is correct answer.

Explanation of Solution

Given information: 

A line to purchase concert`s tickets moves at the rate of 5 feet per 20 minutes. And a person moves total 30 feet in this line.

Concept used:

Based on given rate, first to calculate total move (in feet) in one minute and then this move will be multiplied by 30 to get the required duration. Or, it is used unitary method here.

Calculation:

As covering 5 feet, takes 20 minutes,

So, covering 1 feet, takes $=\frac{20}{5}$ minutes

or, covering 30 feet, takes $=\frac{20\times 30}{5}=4\times 30=120$ minutes

So, it takes 120 minutes by a person, to move 30 feet in the line.