Taking into account the definition of equation and percentage, 30 percent of 120 is the same as 80 percent of 45.
An equation is defined as an established equality between two expressions, in which there may be one or more unknowns or variables.
So solving an equation consists of finding the value or values of the variables so that they fulfill the equality represented in the equation. That is, when changing the variable for the solution found, the equality must be true.
On the other side, the percentage is a value that represents the proportionality between two established quantities. That is, the percentage tells what part of a total represents a quantity.
Mathematically, the percentage is the division between an initial quantity and the total quantity, all multiplied by one hundred.
And to calculate the percentage of a quantity, the quantity is multiplied by the percentage and divided by 100. Then, 30 percent of 120 can be expressed as: (30×120)÷100
On the other hand, 80 percent of a number can be expressed as: (80×number)÷100
Since 30 percent of 120 must be the same as 80 percent of an unknown number, the following equation can be expressed:
(30×120)÷100= (80×number)÷100
Solving:
3600 ÷100= (80×number)÷100
36= (80×number)÷100
36×100= 80×number
3600= 80× number
3600÷ 80= number
45= number
The, 30 percent of 120 is the same as 80 percent of 45.
Learn more about percentage with this examples:
- https://brainly.com/question/19295956?referrer=searchResults
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