Answer: the old price for 1 liter is $0.3
Step-by-step explanation:
Let x represent the old price for 1 liter of petrol.
Last week a man bought 20 liters at the old price. This means that the total amount that the man paid for 20 liters is 20x.
The cost of petrol rises by 2 cents a liter. This means that the new price per liter is x + 2/100 = x + 0.02
This week he bought 10 liters at the new price. This means that the total amount that the man paid for 10 liters is
10(x + 0.02)
= 10x + 0.2
Altogether, the petrol costs $9.20. This means that
20x + 10x + 0.2 = 9.2
30x + 0.2 = 9.2
30x = 9.2 - 0.2
30x = 9
x = 9/30
x = 0.3
Step-by-step explanation: To solve for x in this inequality,
your goal is the same as it would be if you were solving an
equation, to get x by itself on one side.
Since 5 is being subtracted from x, add 5 to both sides of the inequality.
On the left, the -5and +5 cancel out and on the right, -2 + 5 is 3.
So we have x ≥ 3.
When graphing, start with a closed dot at +3 because x is
not just greater than +3, it's equal to it as well.
Then draw an arrow to the right, like I have done below.
9 x 72 = 9 x ? + 9 x 2
72 = 8 x 9 = 4 x 2 x 9
9 x 72 = 9 x 4 + 9 x 2
number is described as rational if it can be written as a fraction (one integer divided by another integer). A number is irrational if it cannot be written as a fraction. The decimal form of an irrational number does not terminate or recur.
