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Old Jan 31 2010, 06:16 PM
silvia8917 silvia8917 is offline
 
Join Date: Dec 22 2009
Posts: 27
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Quote:
Originally Posted by ElkRiverRancher View Post
Okay .... 8 ÷ 2 x 2 ÷ 2 = what, exactly? Are you going to do the multiplication, first, or the division, first?
Multiplication, first (2 x 2 = 4), then do the division (8 ÷ 4 (= 2) ÷ 2 = 1)

Division, first (8 ÷ 2 = 4) x ( 2 ÷ 2 = 1) = 4

Or, are you going to do the equation in order 'left to right'

8 ÷ 2 (= 4) x 2 (= 8) ÷ 2 (= 4)

Seems to me that if you 'speak' this equation in a sentence stream

"Eight divided by two times two divided by two" the only way the human mind is going to keep up is by doing the equation in the order in which the numbers are received. You're going to calculate as you receive the information, so you're going to 'see' 8 , divide it by 2 and 'register' 4, then multiply 4 by the next number your brain receives (2), register "8", then divide 8 by "2", and get a result of 4, at the end of the stream of numbers.

My first Texas Instruments hand held calculator (and several I still have) use the obelus as the division symbol, and the lower case 'x' as the multiplication symbol.


BTW, my 'simply' arithmetic 'employment test' is a 'word problem':

"My vineyards yield 525 quarts of grapes. There are 105 quarts of grapes in every dry barrel of grapes. Each dry barrel of grapes yields 2 gallons of wine. How many gallons of wine will my vineyards yield?"

So, teach, what would be your answer?
As multiplication and division belong to the same class, just see if there're brackets. If yes, follow the brackets; if no, do it from left to right.

Actually "eight divided by two times two divided by two" is ambiguous? As it is possible that the second "divided" is applied to "eight divided by two times two", or to only the "two" before it. It can be read as: eightdividedbytwo - times - twodividedbytwo. Just a thought.

As for your word problem, 525/125 * 2 = 5*2 = 10. Right? In writing it'd be 525 ÷ 125 x 2 = 5 x 2 = 10

(Why are we discussing math in this thread anyway. LOL Though math is undoubtedly useful in calculating which crops is the most ludicrous in Farm Town. )
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