## gahm8684 one year ago This is the excercise: (363 × 1.48)/3.5-1.79 + 6.1 × 10^−1 However, my question is unralated the answer. Does 10^-1 out as a significant figure? and if it does, it would count as 1 digit, right?

1. jdoe0001

hmmm what's the question again?

2. Hero

Write 10^{-1} as a decimal, then it should be obvious to you.

3. gahm8684

$(\frac{ (363*1.48) }{ 3.5-1.79 })+6.1*10^{-1}$

4. gahm8684

0.1

5. jdoe0001

$$\bf a^{-{\color{red} n}} \implies \cfrac{1}{a^{\color{red} n}}\qquad \qquad \cfrac{1}{a^{\color{red} n}}\implies a^{-{\color{red} n}} \\ \quad \\ % negative exponential denominator a^{{\color{red} n}} \implies \cfrac{1}{a^{-\color{red} n}} \qquad \qquad \cfrac{1}{a^{-\color{red} n}}\implies \cfrac{1}{\frac{1}{a^{\color{red} n}}}\implies a^{{\color{red} n}}$$

6. gahm8684

so does count as significant, and it is 1 digit

7. gahm8684

Thanks again

8. gahm8684

My last question is ames Street, QB 1968-69, led Texas to the National Championship in 1969. His 20 straight victories as a starter are still the best in SWC history. How many significant digits does 20 represent? 1. 1 2. 2 3. impossible to determine 4. 0 5. infinite

9. gahm8684

I know 20 has 1 digit, but how do i know is not a tricky question and they mean 20.00000 which has infinite digits

10. gahm8684

I meant 20 has 2 digits

11. Hero

You interpret 20 as 20 not 20.00000

12. Hero

And they're asking for the number of significant digits the number 20 has.

13. Hero

Decimals apply mostly with measurement. 20 in this case is the result of "counting" not "measurement".

14. Hero

Technically, counting is a form of measurement, but you wouldn't use decimals for counting whole numbers.

15. gahm8684

But if it was a measurement i would've being like 20.000..... right?

16. gahm8684

no, it was actually infinate

17. gahm8684

but what you're saying make sense

18. Hero

This is one of those "I believe button" type concepts because logically it doesn't make sense, at least not to me, but apparently, "Exact numbers have an infinite number of significant digits".

19. Hero

I would have picked 1 significant digit which would have been supposedly wrong.

20. gahm8684

Yeah, i get what you are saying, and it makes perfectly sense. On tuesday I will tell my teacher to explain me more about this. I think it is a tricky question

21. gahm8684

Thank you so much anyway

22. gahm8684

have a good weekend