- Concept Videos
- Solutions 44

Calculate to the correct number of significant figures.

b. (5.01 X 10^{5}) ÷ (7.8 X 10^{2})

Hey guys, here we're going to calculate the answer to the correct number of significant figures, so what they give us here is 5.01x10^5 divided by 7.8x10^2 so notice here that they're given to us in parenthesis and it's always a good idea when you input this into your calculator because it's times 10 to a power you should put it in parenthesis otherwise your calculator may give you the incorrect answer, now remember when you're multiplying or dividing the answer has to be the one with the least number of significant figures, here this number has a decimal so we're going to go from left to right, the first non-zero numbers is where we begin counting, here's my first non-zero number count all until you get to the end, so 1 2 3 sig figs here, now here place again so go from left to right here my first non-zero number count all the way until you get to the end 1 2 so your answer has to have 2 significant figures at the end so when you punch this into your calculator you get 642.308 this answer here has more than 2 sig figs so we're going to change it into scientific notation so we want 2 digits left at the end when we write our answer, we're going to say next to that 4 is a 2 because it's less than 5 we don't round up that 4 season stays a 4 so changing it into scientific notation we get 6.4x10^2 so that will be our answer to the correct number of significant figures.