This can only be estimated as you will be charged a commission for exchanging yen into dollars or vice versa, and each financial institution will have their own daily rate for making the exchange. Also the currency markets are very fluid and the pairs are always moving against each other.
You should take the mid market rate of exchange between any currency pair for the day in question. This is exactly half way between the sell rate and the buy rate for that currency pair on the financial markets. You are likely to be charged between 3% and 6% commission if you exchange currencies, so this cannot be exact, but it will give you a very good estimate. You are likely to be charged more in commission if the yen and dollar are very volatile against each other on the day you make the exchange, as the bank will be unsure what the value is and will leave themselves plenty of leeway.
Today the USD/JPY (US dollar to Japanese yen) mid-market rate at 5.31 am UTC was 95.95 yen to the dollar. This means at this point, according to the mid-market rate, 10,000.00 yen was worth $104.22.
This may be different tomorrow and was probably different yesterday, according to how the exchange rate varied on the currency markets.
If you regularly need to know exchange rates, as I do, to account for my British social security to the IRS, then you cannot do better than refer to www.xe.com
This site has all the major currency pairs on its home page plus a widget which will convert any amount from one currency to another for you at current day rates. If you go further into the site, it has a historical table of every currency in the world for every date going back years plus a widget to convert any specific amount from any one currency to any other currency that you choose for any date you select. It is absolutely brilliant and I cannot recommend it highly enough.
If you actually go to a bank and convert yen to dollars the amount you get will never be quite as much as the mid-market rate because of the commission the bank will take to fulfill the transaction unless, of course, the yen rises against the dollar between the time you look up the exchange rate and the time you get to the bank! But the mid-market rate is an excellent guide and the best figure to use if you are accounting to an official body such as the IRS.
This is a time of great volatility of the US dollar against other currencies, so keep an eye on the exchange rates if you need to know the value of the dollar against the yen on a regular basis. It is exceedingly fluid at the moment!