What do you remember about the difference between canadian and us dollar (which one is greater)? also, explain which online tool would you use to convert 10 canadian dollars into us dollars and how much usd will you get?

The American dollar is worth 1.28 as of the moment I'm writing this. There are many places that will quote this conversion. I use kitco. The official exchange is from the bank of Canada. Whatever you do if you need to exchange money or spend in the States, use a credit card. You will lose a couple of pennies per dollar but that by far is the easiest way to go. All credit cards have 800 numbers. Check every few days to see what you owe them and pay it immediately. Make sure you set up your bank account so you can pay either by phone or on the internet. 

Given the exchange rate I've quoted (they usually give it to 4 digits). You could set up a proportion that looks like this.

US dollars / Canadian dollars = Exchange rate / 1
x / 10 = 1/1.28 Cross multiply
1.28 * x = 10
x = 7.81 US dollars

That's a big beating when you are paying a motel bill.

Oh! This is just a math question. Are you travelling or are you just asking? My answer is for just asking.