30 is 40% of what number

30 is 40% of what number

The Correct Answer and Explanation is:

To solve for the number where 30 is 40% of it, you can set up the equation: 30=0.40×X30 = 0.40 \times X30=0.40×X

Here, XXX represents the unknown number, and 0.400.400.40 is the decimal form of 40%.

Now, to isolate XXX, divide both sides of the equation by 0.40: X=300.40X = \frac{30}{0.40}X=0.4030​ X=75X = 75X=75

So, the number you are looking for is 75.

Explanation:

The concept of percentages can be understood as a way to express a number as a fraction of 100. In this case, 40% means 40 out of every 100 units, or 40100=0.40\frac{40}{100} = 0.4010040​=0.40.

To find out what number 30 is 40% of, we need to set up a proportional relationship. The statement “30 is 40% of X” means that when you take 40% of XXX, you get 30. Mathematically, this translates into: 30=0.40×X30 = 0.40 \times X30=0.40×X

By solving for XXX, we are essentially asking, “What number, when multiplied by 40%, equals 30?” Dividing 30 by 0.40 gives us 75. Therefore, 30 is 40% of 75.

This method of solving percentages is very common and can be used in various real-life scenarios, such as calculating discounts, tax rates, or even determining how much of a substance is present in a solution based on a given concentration.