Table of Contents
1 Proportions
1.1 Exercises
1.1.1 Problem set
For each of the following problems, identify also if the relationship between the independent and dependent quantities is a proportion.
- Say, you are doing a summer job. Your goal is to earn a certain amount of money so that you could buy a computer for yourself. What is a good independent quantity that the money you earn depends on?
- A pediatrician wants to understand a child’s growth by checking the height of the kid over time. What is the independent quantity that the dependent quantity height relates to?
- A family is planning a vacation to Orlando, and is estimating how much it costs them for hotel stay on the trip. What is a good independent quantity that the cost could be related to?
- A paving company is estimating the time it would take to pave a street. What is a good independent quantity that time it takes to pave could be related to?
- A city council is making certain plans for the city development based on how the population of the city grew over time in the past. What is a good independent quantity that population of the city could be related to?
1.1.2 Problem set
For each of the following problems, determine the independent quantity based on the question asked. Then, explain the meaning of unit rate in the problem’s context and find the value of the unit rate.
men are able to paint
square feet of walls in a day. How many men are required to paint
square feet of walls in a day?
- To pave a
m long road in a day, it takes
machines. How many machines does it take to pave a
m long road in the same amount of time?
backpacks cost
. How many backpacks could I buy with
?
- During a hurricane relief,
tonnes of grain were required to support an affected neighborhood with
families. How many tonnes of grain are required to support a neighborhood of
families?
high school students are able to arrange books in
bookshelves in one hour. How many bookshelves can
students arrange in one hour?
- A landlord makes
per year by renting out
condo units.
- How much money will he make per year if he rents out
condo units?
- If he needs to make at least
per year, how many condos must he rent out?
- How much money will he make per year if he rents out
- A car drives
miles on
gallons of gas.
- How many miles can be driven on
gallons of gas?
- How many gallons of gas are required to drive
miles?
- How many miles can be driven on
1.1.3 Problem set
high school students are able to arrange books in a library in
hours. How many hours do
students need to arrange the library books?
- A service organization stores food in their pantry . It estimates if the pantry is full, the food in there is sufficient to feed
people for
days. At one particular time, the organization is required to house
people. How many days would the food (from the pantry that is full) last feeding all the
people?
- It takes
machines
days to pave a road. How many machines are required to pave a similar road in
days?
- It takes
days for
painters to paint the interior of a house. How many days would it take for
painters to paint the interior of a similar house?
1.1.4 Problem set
- A car going at
mph is able to cover a certain distance in
minutes. How much time will a car going at
mph take to cover twice that distance?
- Sam runs at
mph, while Jack runs at
mph. They both are running along the same loop in a park. What is the proportion of time taken by Sam to the time taken by Jack?
1.1.5 Problem set
- It takes
machines
days to pave a
m long road. How many machines does it take to pave a
m long road in
days?
- It takes
men
days to paint a
sq. ft wall. How many sq.ft of the wall can
men paint in
days?
- It takes
men
days to paint a
sq. ft wall. How many days will it take
men to paint
sq. ft. wall?
- It takes
men
days to plant seeds in a
sq. ft. field. How many days does it take for
men to plant seeds in a
sq. ft. field?
- Marvin can mow a yard in
hours. If Marvin and Tim work together, they can finish the mow in
hours. If Tim works by himself, how long would it take for Tim to mow the yard?