Me and a friend had a dispute over the answer to this question today. The scenario is:
If you got $1\%$ of iPhone sales (Assuming $\$900$ in Canadian Dollars), how much would you make over Ten Million ($10{,}000{,}000$) sales?
We have two answers, and each believe we are correct.
I believe the following:
$1\%$ of $900$ is $9$. $9$ times $10{,}000{,}000$ equals $90{,}000{,}000$. So you would make $\$90{,}000{,}000$ over Ten Million Sales. Alternatively, you could do $900\times 10{,}000{,}000 = 9{,}000{,}000{,}000$ (Nine Billion) and $1\%$ of $9{,}000{,}000{,}000$ is Ninety Million Dollars.
My friend believes that the answer would be $81{,}000{,}000$ using the standard steps to calculate percentage. Although I believe he got the math wrong, (Multiplying by $0.09$ instead of $0.01$) he insists he is correct.
Who is correct between us?
Best Answer
$$Percent \times price \times units = 1\% \times $900 \times 10,000,000 = $90,000,000$$