# Weird-Confusing mistake in subtraction result!!!!

3 views (last 30 days)
shirin mhd on 25 Aug 2022
Moved: Matt J on 25 Aug 2022
Hi everyone
I have a weird problem with a simple subtraction.
Here is my code. I define 'R' and 'a1 to a8':
R=194067676.886295
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
a1=19044444.410581;
a2=15000000.000000;
a3=1500000.000000;
a4=4000000;
a5=500000;
a6=32323232.475714;
a7=120000000;
a8=1700000;
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
sum=a1+a2+a3+a4+a5+a6+a7+a8
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
d=sum-R
As you can see from the result below, the value of 'R' and 'sum' is the same.
I expect the subtraction of 'R' and 'sum' which is 'd', becomes zero.
But as you can see, it isn't zero and I don't understand why is this happening.
result:
R =
1.940676768862950e+08
sum =
1.940676768862950e+08
d =
2.980232238769531e-08
I'm really confused.

Stephen23 on 25 Aug 2022
Moved: Matt J on 25 Aug 2022
shirin mhd on 25 Aug 2022
Moved: Matt J on 25 Aug 2022
I really appreciate your taking the time to explain the concept and share links. Im a novice coder and I'm learning a lot from here. Thank you for your help.

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