My textbook says evaluate $7 + 4 \times 8$ in a revision course. Is it $7 + 4$, then multiply by 8 or $7 + (4 \times 8)$ ? The calculator automatically gives me the correct answer, so I am going to assume there is a universal rule for this.
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See http://math.stackexchange.com/questions/33215/what-is-48293/33238#33238 – Gerry Myerson Feb 23 '14 at 09:12
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http://en.wikipedia.org/wiki/Order_of_operations – Feb 23 '14 at 10:12
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"The calculator automatically gives me the correct answer" A scientific calculator would give you an answer of 39, but try a simpler calculator (a four-function calculator, or a simple cellphone calculator) and see if you get the same answer. – JRN Feb 23 '14 at 12:28
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By order of operations, the answer is $7+32 = 39$. You do multiplication first, then addition.
Euler....IS_ALIVE
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Remember BEDMAS; the order of operations.
$\ \ \ \ \text{B - Brackets}$
$\ \ \ \ \text{E - Exponents}$
$\begin{cases} \text{D - Division (can be done with multiplication)} \\ \text{M - Multiplication (can be done with division)} \\ \end{cases}$
$\begin{cases} \text{A - Addition (can be done with subtraction)} \\ \text{S - Subtraction (can be done with addition)} \\ \end{cases}$
There are no brackets, nor exponents. The first step would be to multiply. $4\times 8=32$. Then, the next step would be to add. $7+32=39$.
Answer:
$$\displaystyle \boxed{7+4\times 8=39}$$
Anonymous Computer
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