Algebra.... Answer should be 0?

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Discussion Overview

The discussion revolves around a mathematical expression involving multiplication and division of small numbers, specifically the calculation of 0.0162 * 0.000000000000002 divided by 0.000054 * 0.02. Participants are attempting to determine the correct answer and clarify the calculation process.

Discussion Character

  • Homework-related
  • Mathematical reasoning
  • Technical explanation

Main Points Raised

  • Some participants express confusion about obtaining a result of 0 when calculating the expression, questioning the correctness of their calculators.
  • One participant suggests using scientific notation to simplify the calculation, providing a reformulated version of the expression.
  • Another participant indicates a lack of understanding of how to solve the problem without a calculator and requests a simplification for learning purposes.
  • Some participants emphasize that a fraction can only be 0 if the numerator is 0, arguing that since none of the numbers in the expression are 0, the result cannot be 0.
  • A participant shares their calculator's output, which is a very small number, and suggests multiplying by 10^15 to eliminate decimal points for easier computation.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the correct answer, and there are multiple competing views regarding the calculation process and the interpretation of results. Some express frustration with their calculators, while others focus on the arithmetic principles involved.

Contextual Notes

There are limitations in the discussion regarding the assumptions made about calculator functionality and the understanding of scientific notation. Some participants may not fully grasp the arithmetic concepts necessary to resolve the problem.

jangoom
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0.0162 * 0.000000000000002 divided by 0.000054 * 0.02

I keep getting 0 but when I try to see if its correct, it tells me its not. What the heck is the answer?
 
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jangoom said:
0.0162 * 0.000000000000002 divided by 0.000054 * 0.02

I keep getting 0 but when I try to see if its correct, it tells me its not. What the heck is the answer?
You are putting this into a calculator, aren't you?

Try this: use Scientific notation for these. Your problem now becomes:
[math]\frac{1.62 \times 10^{-2} \cdot 2 \times 10^{-15}}{5.4 \times 10^{-5} \cdot 2 \times 10^{-2}}[/math]
(I think I got the zeros right.). Now all you need to do is calculate
[math]\frac{1.62 \times 2}{5.4 \times 2} \times \frac{10^{-2} \times 10^{-15}}{10^{-5} \times 10^{-2}}[/math]

-Dan
 
Im still getting 0... to be honest sir I don't know how to solve it without a calculator... could you simplify this so I could learn? I need the answer as well but I need to learn how since I will have a test soon over this..
 
jangoom said:
Im still getting 0... to be honest sir I don't know how to solve it without a calculator... could you simplify this so I could learn? I need the answer as well but I need to learn how since I will have a test soon over this..
What part do you not know how to do?

Put [math]\frac{1.62 \times 2}{5.4 \times 2}[/math] in you calculator.

Now work this part out: [math]\frac{10^{-2} \times 10^{-15}}{10^{-5} \times 10^{-2}}[/math]

Hint: [math]10^{-x} = \frac{1}{10^x}[/math].

Can you finish from here?

-Dan
 
jangoom said:
0.0162 * 0.000000000000002 divided by 0.000054 * 0.02

I keep getting 0 but when I try to see if its correct, it tells me its not. What the heck is the answer?
What type of calculator are you using?

It must be really primitive if it reads 0.000000000000002 as 0 (zero).
All recent calculators accept it as 2 \times 10^{-15}.
 
In basic arithmetic, you should have learned that the only way a fraction can be 0 is if the numerator is 0 and that the only way a product of numbers can be 0 is if at least one of the numbers is 0. Here, none of the given numbers is 0 so the result cannot be 0. Please do not let using a calculator be a substitute for learning arithmetic!
 
My cheap calculator gives:
.000 000 000 000 012
or: 1.2e-14

0.0162 * 0.000000000000002 divided by 0.000054 * 0.02

If it makes easier, multiply each by 10^15 (gets rid of decimal points):

16,200,000,000,000 * 2 / (54,000,000,000 * 20,000,000,000,000)
 
Last edited:

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