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Quite simple for you Math Genius but I'm struggling to understand the following equation. (I've only just started an introductory course in Mathematics and I'm keen to learn) :)

I'm getting 2 answers

On my scientific Calculator $= 5.4$

On this website $= -5985$

My formula below. First I would like to know which one is correct or an explanation as to why they can both be correct. if someone could then break it down for me so I can understand where I have gone wrong.

$$10+6\cdot-\frac{8}{2(-25)}\cdot(-10)+5=$$

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To be honest the mistake seems to lie somewhere within the interpretation of your given parenthesis hence it is not clear at all. The website you are refering to interprets your input as

$$10+6\cdot-\frac{8}{2}(-25)\cdot(-10)+5=-5985$$

where on the other hand you are asking for the evaluation of

$$10+6\cdot-\frac{8}{2(-25)}\cdot(-10)+5=5.4$$

The simple mistake is that the calculator you used online did not know that the $(-25)$ belongs to the denominator. Therefore use more parenthesis to make sure what you want to be computed.

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  • $\begingroup$ To be honest I didn't know the (-25) belonged to the denominator. Stupid question again but should you not calculate 8/2= ans(-25)= $\endgroup$ – Pedro Bernardo Oct 2 '18 at 10:44
  • $\begingroup$ As I already mentioned it is a question of interpretation hence you seem to be unsure for yourself could you maybe add where this task came from? What exactly do you mean with $8/2=\operatorname{ans}(-25)$? $\endgroup$ – mrtaurho Oct 2 '18 at 10:47
  • $\begingroup$ I understand what you mean in regards to interpretation. $\endgroup$ – Pedro Bernardo Oct 2 '18 at 10:51
  • $\begingroup$ I understand what you mean in regards to interpretation. But based on my initial calculation which was 10+6*-8/2(-25)*-10+5 until a moderator changed it to look like the above, is there any correct way of tackling the mathematical calculation(in its simple form) or is it based purely on interpretation? Because that would mean the calculation is formed wrong and is open for interpretation? is that correct? if i'm confusing you even more then don't worry about it, I will speak to my tutor about it.:) $\endgroup$ – Pedro Bernardo Oct 2 '18 at 11:01
  • $\begingroup$ I edited your question ^^' The problem about "10+6*-8/2(-25)*-10+5" is that it is not clear where the $(-25)$ belongs to. And so yes, it is only a question of interpretation. One could write "10+6*-8/(2(-25))*-10+5" to make clear it belongs within the denominator or leave it as it was and so it would be likely to be interpreted as $(-25)$ within the nominator. Both interpretations are possible and lead to your two provided solutions. I guess you have to ask your tutor to make things clear. $\endgroup$ – mrtaurho Oct 2 '18 at 11:06

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