Using Sig Figs
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Using Sig Figs
This may be kind of a simple question, but I have seen problems use measurements with only one sig-fig (ie. 100g). According to sig fig rules would you only use one sig fig for the remainder of the problem? Technically it is following the rules, however it creates a large discrepancy from your answer to one if you used more sig figs.
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Re: Using Sig Figs
Hello!
According to significant figure rules, the answer to a problem with one significant figure should also have one significant figure. I know it kind of sucks, because your answer may end up being way off, but that's the way I have always been taught. For example, if you had 3700x100, the answer when using significant figures would be 400,000 to maintain that one significant figure.
According to significant figure rules, the answer to a problem with one significant figure should also have one significant figure. I know it kind of sucks, because your answer may end up being way off, but that's the way I have always been taught. For example, if you had 3700x100, the answer when using significant figures would be 400,000 to maintain that one significant figure.
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Re: Using Sig Figs
The number of sig figs in the answer is determined by the number with the lowest number of sig figs used in the calculation. So there will be a large discrepancy if you follow this sig fig rule, especially if you use larger numbers with lots of zeros to the right of the sig fig.
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Re: Using Sig Figs
When adding or subtracting, you use the same amount of significant figures from the number with the most amount of sig figs. When multiplying or dividing, you do the opposite where you use the same amount of sig figs from the number with least amount of sig figs. I know its a little confusing but it gets easier to remember the more you do it.
Re: Using Sig Figs
Sig. Figs are determined by the amount that you start with so lets say you had 200g the amount of sig figs you would have is 1 because the rule is that trailing zeros are not considered sig figs.
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Re: Using Sig Figs
The number of sig figs you use will always be determined by the number with the lowest sig figs in the calculation, so if it's 1, then your answer must use 1 sig fig.
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Re: Using Sig Figs
Although it may be a large discrepancy, the lowest sig fig in the problem or calculation will always determine the number of sig fig in the answer. However, during the process of calculations, you can use as many sig figs as you want. It's the final answer that counts.
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Re: Using Sig Figs
Hi! I'm not entirely sure, but I think a method to get the most accurate answer would be to continue calculating without rounding your answers, then rounding to the same number of significant figures at the very end. For example, if the problem was presented with two significant figures and your calculations have a different amount of sig figs, you can continue on and simply round at the very end. This way, the answer would be more accurate. However, I'm pretty sure for certain questions, there will be a range of answers accepted (ex. 3.8 ≤ answer ≤ 4.2). People round at different points in their calculations, so there may be some kind of leniency when it comes to the final answer.
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Re: Using Sig Figs
I agree that the sigfigs are always determined by the lowest sigfig number when multiplying/dividing, even if it is one sigfig and makes the calculation seem off. When adding and subtracting though, it is determined by the number with the least amount of decimal places. I find that it's pretty uncommon to have a solution to a problem that is reduced to one significant figure and is drastically different from the number you initially calculated.
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Re: Using Sig Figs
Using sig fig rules, you would have to round your final answer answer to a single sig fig. Throughout the problem you can carry a few extra sig figs to make your final answer more accurate
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Re: Using Sig Figs
I believe you don't have to use one sig figs for the rest of the problem, but your final answer has to be in one sig fig.
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Re: Using Sig Figs
Leading zeros do not count as a sig fig, only in between zeros and ending zeros count as sig figs.
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Re: Using Sig Figs
To put it simply: Yes, you'd round your answer to a single sig fig and yes, it'll probably cause large disparities between your solution and what is accurate, but I'm pretty sure you're still able to go through and solve the question with extra sig figs.
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Re: Using Sig Figs
You don't only use one sig fig in the remainder of the problem but you do for the final answer. You should perform calculations with the numbers given to reduce round-off error and then reduce the final answer to one sig fig if it's multiplication/division. If it's addition/subtraction, i think you're supposed to change the answer to the number of decimal places. Like if you 0.16-0.01, your final answer would be 0.15 because 0.01 has two decimal places even if it's one sig fig. Hope that helps!
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Re: Using Sig Figs
If the problem is only using one sig fig than I pretty sure then you have to use only sig fig for the remainder for the problem even though it might create a rounding error. The answer you get should still be the answer the textbook got because they continued the problem with one sig fig. If you choose to do more than that they you will get a different answer and therefore get the problem wrong.
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Re: Using Sig Figs
Always use the lowest amount of sig figs just for the answer not the rest of the problem.
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Re: Using Sig Figs
The number of sig figs used in your answer is dependent on the information given with the lowest number of sig figs. Although it creates accuracy issues, it is the way the system works.
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Re: Using Sig Figs
According to sig fig rules, your answer must have only one sig fig. Usually, you would not round at every step in the problem as that is what causes the huge discrepancy between using one sig fig and using more than one sig fig.
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Re: Using Sig Figs
Sig Figs is based off the smallest amount of sig figs in a given number. However, I would avoid using sig figs during calculations and only use sig figs at the very end!
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Re: Using Sig Figs
Though it may seem inaccurate or incorrect, you should always refer to the least amount of sig figs. If this is 1, like you mentioned, then the answer should also be one sig fig. I haven't come across too many problems in which only one sig fig was used, but it's definitely a rule to keep in mind!
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Re: Using Sig Figs
The descrepancy is supposed to be there. They know you will/should be using sig fig rules, so they are accounting for that.
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Re: Using Sig Figs
Hi Samuel!
Technically, you should continue to just use one significant figure in problems like this, despite the issues it may cause.
Technically, you should continue to just use one significant figure in problems like this, despite the issues it may cause.
Re: Using Sig Figs
I dont think sig figs will be a big topic on the final, but if a number doesn't have a decimal point at the end of it and has zeros like 100, it is only one sig fig.
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Re: Using Sig Figs
I know it's a strange answer, but yes. Your answer may seem inaccurate, but the number of sig figs used is determined by the number with the lowest sig fig count.
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