Math quiz; Who is right?

[Martinet]

Who is right?

230 - 220 ÷ 2 =

I say it is 120

A math PhD says it is 5!

 

[Oberst]

5

 

[TomD]

Actuary says 120. Division takes precedence in the equation order. You can enter it in a spreadsheet to verify.

 

[PaD]

120
I was taught that there is an order of operations and I thought that was still the rule.
Strange answer from a math PhD. Age?
Why not use parentheses? That’s an easy way to show how the problem is meant to be solved.

 

[Oberst]

120
I was taught that there is an order of operations and I thought that was still the rule.
Strange answer from a math PhD. Age?
Why not use parentheses? That’s an easy way to show how the problem is meant to be solved.

I was thinking the same thing about parentheses.

 

[Martinet]

Harvard PhD candidate wanted to know where the PhD was from.

 

[harryS]

I was born in the 1940's and learned my math scratching a rock on a coal shovel. I get 110.

Take 79 bicycle helmets and add 40 more. That's 119. Now subtract your age. If the answer was the last two digits of the year you were born, you deserve to own an ebike for your birthday. If it wasn't then you already had your birthday. Did you get an ebike?

 

[Martinet]

I was born in the 1940's and learned my math scratching a rock on a coal shovel. I get 110.

Take 79 bicycle helmets and add 40 more. That's 119. Now subtract your age. If the answer was the last two digits of the year you were born, you deserve to own an ebike for your birthday. If it wasn't then you already had your birthday. Did you get an ebike?

Weather is a little cold here, so I'll stick to high-low poker for now. [hint]

 

[onlineaddy]

Was that PhD bought from an online university?

 

[Martinet]

Was that PhD bought from an online university?

PhD from UNLV in probability and gambling theory.

 

[Over50]

Who is right?

230 - 220 ÷ 2 =

I say it is 120

A math PhD says it is 5!

Both could be correct (dependent on the calculator)? Of course a human using math or most calculators will respect the order of operations (just put it in Excel as you wrote it and the answer is 120....Python too). But I think there are some programming languages out there that operate simply on a left to right basis. In which case the answer is 5.

 

[PaD]

”Smokey this is not ’Nam, this is math. There are rules.”

 

[Martinet]

Given the "normal" order of calculations, they were BOTH right.


120 = 5!

My apologies to anyone who is unfamiliar with factorials.

 

[steve marino]

You subtracted 220 from 230, and that left you with 10. Divide that by 2 and you get 5.

 

[Marci jo]

Must be a slow winter’s day on this forum.
What does any of this have to do with ebikes?

 

[Bigal1463]

The answer is 5. Take 220 away from 230 and you get 10, then divide it by 2 and the answer is clearly 5. How are you people getting a something other than 5? It’s basic arithmetic.

 

[ChezCheese:)]

Without parentheses, shouldn't operations be done in the order they come, from left to right, like reading a sentence? Thus 5 is the right answer. If there were parentheses indicating which operations to do first, then the answer would be different, ie, 110.

 

[Deacon Blues]

Apparently, some of you missed the math class that talked about order of operations.
There is no such thing as 'normal' order of operations. There's order of operations...period. Calculators are a tool, but must be used properly to get the correct answer.

I taught math for 34 years and the answer is 120. The math PHD is wrong.

 

[Martinet]

Apparently, some of you missed the math class that talked about order of operations.
There is no such thing as 'normal' order of operations. There's order of operations...period. Calculators are a tool, but must be used properly to get the correct answer.

I taught math for 34 years and the answer is 120. The math PHD is wrong.

5! = 5 factorial = 5x4x3x2x1= 120

 

[ChezCheese:)]

Math class? Math class was half a century ago!