# Math Help - How do I calculate a percentage that is above 100%?

I need help calculating a percentage that is more than 100%. Here is the main portion of the problem: "The arenas alone have ended up costing nearly 300 percent more than was planned - nearly $4 billion total and growing." I can't figure out how to determine what 4,000,000,000 is 300% of. Please help. Thank you, ondverg 2. ## Re: How do I calculate a percentage that is above 100%? Originally Posted by ondverg I need help calculating a percentage that is more than 100%. Here is the main portion of the problem: "The arenas alone have ended up costing nearly 300 percent more than was planned - nearly$4 billion total and growing." I can't figure out how to determine what 4,000,000,000 is 300% of. Please help.

Thank you,
ondverg
per cent means per 100 so

P% of X is (P/100)X

so 300% of X is (300/100)X = 3X

we have here that 300% X = 4000000000 so

3X = 4000000000

X = 4/3 x 1000000000 ~ 1.33 x 109

3. ## Re: How do I calculate a percentage that is above 100%?

Thank you for helping me, romsek. I want to make sure I asked the question right. So, if the arenas cost more than was originally planned, then the original cost should have been 1 billion dollars and the 300% increase makes it 4 billion dollars? The 1.33 x 10^9 is confusing me. Does this mean that the original cost should be 1,333,333,333.00 and not 1,000,000,000.00?

ondverg

4. ## Re: How do I calculate a percentage that is above 100%?

yes. 1 and 1/3 billion dollars instead of 1 billion, i.e. \$1,333,333,333.00

(1 1/3)x3 = 3 3/3 = 4

5. ## Re: How do I calculate a percentage that is above 100%?

Okay, I got this time! Thanks again, romsek. :-)

6. ## Re: How do I calculate a percentage that is above 100%?

In general "A percent of B" mean $\frac{A}{100}\times B$. Given that "4 billion dollars is 300% move than was planned" and letting "B" represent "what was planned" that can be written $\frac{300}{100}\times B= 4,000,000,000$ which is the same as 3B= 4,000,000,000 and we can find B by dividing both sides by 3

7. ## Re: How do I calculate a percentage that is above 100%?

Thanks, HallsofIvy.

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