petrol price rose from x cents/ liter to y cents/liter. Before the rise, it costs $a t fill my car with petrol. What is the new cost to fill it?
Assuming a is the old cost, then the new cost will be
a * y/x
To calculate the new cost to fill your car with petrol after the price increase, we need to know the initial price per liter, the final price per liter, and the original cost to fill the car.
Let's assume:
- The initial price per liter of petrol is x cents.
- The final price per liter of petrol is y cents.
- The original cost to fill your car with petrol is $a.
To calculate the new cost, we need to determine the number of liters of petrol required to fill the car before and after the price increase.
Before the price increase:
Let's assume the number of liters required to fill the car before the price increase is L1.
The original cost to fill the car is $a, so we have:
$a = L1 * (x cents/liter)
After the price increase:
Let's assume the number of liters required to fill the car after the price increase is L2.
The new cost to fill the car can be calculated as:
New cost = L2 * (y cents/liter)
To find L2, we have to consider that the price per liter has increased:
L1 * (x cents/liter) = L2 * (y cents/liter)
Now, let's solve the equation to find L2.
First, divide both sides of the equation by (y cents/liter):
L1 * (x cents/liter) / (y cents/liter) = L2
L2 can be calculated as:
L2 = L1 * (x/y)
Finally, we can find the new cost to fill the car by substituting L2 into the equation:
New cost = L2 * (y cents/liter)
By performing these calculations, you can determine the new cost to fill your car with petrol after the price increase.