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Dov Breuer
8,268 PointsSomeone please explain to me how this equals 20? let y = 25 - 5 * 2 + 5
I do not understand how come this equals 20
let y = 25 - 5 * 2 + 5 To me the results should be as follows: 5*2 = 10 10+5 = 15 15-25 = -10
What am i missing?
3 Answers
Ricothe Chen
4,210 Pointssince you multiply first you forgot the minus sign in front of 5, it should be -5*2 = -10, then you add up 5, which becomes -10+5 = -5, and you add 25, that leads to 25-5 = 20.
//by adding parenthesis in front of a minus symbol, it changes the symbol "+" --> "-" within 25 - 5 * 2 + 5 =25-10+5 = 20-(10-5) =25-5 =20
or
25-(5*2)+5</br> =25-10+5</br> =15+5</br> =20
Keith Brantley
6,137 PointsP.E.M.D.A.S.
Diwesh Saxena
15,512 PointsSimplest rule to remember : BODMAS
B : Brackets O : Parenthesis D : Division M: Multiplication A: Addition S: Subtraction
This is Highest to lowest precedence and left to right ... :)
So to answer your question :
25 - 5 * 2 + 5 = 25 - (5 * 2) + 5 = 25 - 10 + 5 = (25 -10) + 5 = 15 + 5 = 20
Jorge Solana
6,064 PointsJorge Solana
6,064 PointsJust think like a machine. Just get binary operations one by one, always reading from the beginning. So in that formula you say: 25 - 5 * 2 + 5, we always start to read from left looking for precedence operators in order like this:
25 - 5? No // 5 * 2? YES! (So do the math and don keep reading) // 10 + 5? No, so we don't find any more high level operators and have to go for the lower level ones...
25 - 10? Yes (So do the math and keep going) // 15 + 5? Yes (So do the math) // And no more instructions. So we got the final result: 20.
I just wanted to make it look more simple as Michael Chen used the minus operator in his explanation (which is of course valid too).
Hope it helps.