You'll need to use the Order of Operations to solve this problem. They are Parenthesis, Exponents, Multiplication, Division, Addition, Subtraction (Please Excuse My Dear Aunt Sally). Multiplication/Division have the same weight, so you read it from left to right. Same with Addition/subtraction.
For this problem, you see there are no parenthesis or exponents, so you move right to multiplication/division. Reading from left to right, the first thing you see is 240/20. Evaluating that comes out to 12. Now you have 12*6 (assuming the x is a multiplication symbol), which evaluates to 72. 72-13=59, and 59+41=100.
Written another way:
240/20*6-13+41
12*6-13+41
72-13+41
59+41
100
I've never heard of "Please Excuse My Dear Aunt Sally". But it's along the lines of "BEDMAS". Brackets, Exponents, Division, Multiplication, Addition, Subtraction. Having said that, the answer should be 18.
240/2-*6-13+41
12*6-13+41
72-13+41
72-54
18
The issue with this solution is that when it comes down to Multiplication/Division and Addition/Subtraction, you need to read them from left to right. They have the same weight, meaning that in reality one doesn't come before the other when it comes to Order of Operations. Therefore, your last 3 lines should be done from left to right. The way you did them is assuming there are Parenthesis (or Brackets) around (13+41). This is incorrect, because (rewritten another way) it should be 72+(-13)+41, or 72 plus negative 13, plus 41. Because addition and subtraction are weighted the same, if you change it all to addition, you'll get the correct answer. Consequently, with multiplication/division, you can rewrite the entire equation as follows: 240*(1/20)*6+(-13)+41 to get rid of all division and subtraction signs (read 240 times one over 20 times 6 plus negative 13 plus 41)...Hope that clears things up!
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