definition: directly proportional
directly proportional means:
when one value increases, another increases at the same rate ↑ ↑
or when one value decreases, another decreases at the same rate ↓↓
example:
sale products and earn money
sale of the same product goes up, earn money goes up
sale of the same product goes down, earn money goes down
calculate:
A car travels 70 miles in 2 hours.
How far would it travel in 5 hours?
problem 1 answer
A factory makes 5 000 items in 6 hours.
How many items could be made in 15 hours?
problem 2 answer
A small airplane can fly 660 miles in 2 hours.
At this speed, how far could the airplane fly in 3 hours?
problem 3 answer
You can buy 4 bananas at the supermarket A for $ 1.08.
You can buy 5 of the same bananas at the supermarket B for $ 1.24
Which place is the better buy?
problem 4 answer
You are paid $ 24 an hour.
How much you earn in 40 hours?
problem 5 answer
A factory makes 80000 items in 5 weeks.
How many items could be made in 2 weeks ?
problem 6 answer
A car travels 70 miles in 2 hours.
How far would it travel in 5 hours?
problem 7 answer
You can buy 6 cakes at the supermarket A for $ 12.40.
You can buy 5 of the same cakes at the supermarket B for $ 11.20
Which place is the better buy?
problem 8 answer
You earn in 80 hours $ 2 240,-.
How much you are paid in 1 hour?