I am trying to do multi step math and keep returning the wrong answer

I am given the equation and this is my code but it keeps telling me that it is returning the wrong value.

b=(1/7)+((72/13)^2)/(sqrt((125/2)-(25/3)))

[Dyuman Joshi]

How is the value wrong?

How precise do you want the output value to be?

[Matthew]

I am in MATLAB grader for a class and don't know what other value I should be getting and wanted someone else to see if I was missing any parentheses or operations.

[Dyuman Joshi]

The expression and the code match, so you are good.

How is the test case in Grader comparing the value with the output?

[Matthew]

Variable b has an incorrect value.

This is all it tells me, I believe she just has a value set that she got from running it. Thank you for looking I will talk to her.

Answer 1

[John D'Errico]

Of course it is wrong. Why did you write 72/13? Why 25/3?

I think you don't understand that

8(1/3) is NOT the same thing as

8 + 1/3

Similarly, you see essentially

5 (7/13)

and you are trying to add fractions!

b=(1/7)+((5*7/13)^2)/(sqrt((125/2)-8*1/3))

b = 1.0799

Do you see what you are doing? When you have an expression like that, you should not assume an implicit addition there. I think you are confused because some people will write

5 1/2

as meaning 5 PLUS 1/2, and thus effectively 5.5.

[Matthew]

I saw those and was thinking mixed numbers not multiplication or addition, thank you for the explanation

[John D'Errico]

Exactly. It took me a few seconds to recognize what you had done. And now that I think of it, I can see the subtle ambiguity. One of those optical illusions in a sense, that you can look at a picture in several different ways.

[Sam Chak]

Also be careful when you guys use WolframAlpha.

Case 1: Without space

Case 2: With space

[Dyuman Joshi]

Even I took them as mixed fractions and responded accordingly. I was going to ask for a clarification but in the mean time John had already answered the question.