Order of Operations Problem

Question

I looked up what the answer was but I'm having a hard time getting to that number...

The value of

(-1)^3+\frac{28}{3}/

can be expressed as - \frac{a}{b}  where a and b are coprime positive integers. What is a+b?

BrushMyQuant · Answer

We will do things inside () first
so (-1)^3 = -1
then things inside  
inside that first multiplication
2/13 * 13/4 = 1/2
then subtraction
-14/3 - 1/2 = -31/6

Now division
-1 + ((28/3)/(-31/6))
= -1 - 56/31
= -87/31 = 87/(-31)

a= 87
b = 31
a+b = 87+31 = 118

Hope it helps!

bazc · Answer

Helps to remember the anagram BODMAS

Bracket Of Division Multiplication Addition Subtraction

Left to right takes priority for when two or more operators are together as in your question.

usre123 · Answer

When the hierarchy of operation is the same, then your allowed to go left to right. Otherwise it's PEMDAS/ BODMAS

PareshGmat · Answer

-1^3 + \frac{\frac{28}{3}}{\frac{-14}{3} - \frac{2}{13} * \frac{13}{4}}

-1 + \frac{\frac{28}{3}}{\frac{-14}{3} - \frac{1}{2}}

-1 + \frac{\frac{28}{3}}{\frac{-31}{6}}

-1 - \frac{28}{3} * \frac{6}{31}

-1 - \frac{56}{31}

-\frac{87}{31}

a+b = 87 + 31 = 118

Order of Operations Problem

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