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# Figure This One Geniuses

#1
10-10-17, 11:01 PM
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Figure This One Geniuses

Seemed so simple yet I did it wrong. Long time since school I guess.

#2
10-10-17, 11:34 PM
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3X = 30
3X ÷ 3 = 30 ÷ 3
X = 10

1X + 2y = 20
10 + 2y = 20
10 + 2y - 10 = 20 - 10
2y = 10
2y ÷ 2 = 10 ÷ 2
y = 5

1y + 4z = 9
5 + 4z = 9
5 + 4z - 5 = 9 - 5
4z = 4
4z ÷ 4 = 4 ÷ 4
z = 1

y + z x X = ?
5 + 1 x 10 = ?
60 = ?

#3
10-11-17, 01:16 AM
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Unless I'm forgetting my algebra rules... seems like it should be 15. No formulas or anything...I almost said 25 til I realized 2 fries vs 1 fry. I don't do math like most other people most of the time. Basically a burger is 5, fries are 1, drink is 10. The rules I learned say * and / first, reading left to right, then + and - , also from left to right. So it's 1 x 10 =10. 5+10=15. It would be different if anything was in parens.

And where the heck did they get these prices? \$10 for a large drink or shake? \$5 for a McDouble or Big Mac? Can't be a Double Quarter since it's only got one cheese slice. Boy...talk about out of touch! lol

#4
10-11-17, 02:20 AM
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drink = 10
sandwich = 5
fries = 2
5 + 2 x 10 = 70

#5
10-11-17, 04:24 AM
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At first I came up with 17 but when I saw the replies I realized I mistook the last x for a +

#6
10-11-17, 04:57 AM
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I did the same thing till I saw the X

#7
10-11-17, 05:39 AM
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60 - the tricky part is counting the double fries as two yet the last line has only a single bag of fries.

Shakes = 10
Burger = 5
Fries = 1

#8
10-11-17, 05:51 AM
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Thanks totally missed that.

#9
10-11-17, 06:03 AM
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Me too! I had to go back and relook at the pic to see what you meant about a double bag of fries.

#10
10-11-17, 06:15 AM
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Genius or not . . . . if you don't pay attention to detail (like the "X"), it doesn't matter which category you place yourself in. I guess that pertains to most everything that we encounter in Life.

#11
10-11-17, 06:22 AM
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Agreed. This looks like an exercise in attention to detail as much as in math.

Going to print it out and give to eight-grader son as "homework" tonight.

#12
10-11-17, 06:35 AM
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Vic is correct... besides the subtlety of 2 fries and the surprise x on the final line, the problem is that most people work math left to right, ignoring the correct "order of operations" on the last line...

When I was in school, order of operations was signified by parenthesis around the operation performed first. But even if the parenthesis is not always there, the rules still apply.

5 + 1 × 10 is the same as:

5 + (1 × 10) is the same as:

5 + 10 = 15.

#13
10-11-17, 06:56 AM
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Couple are almost right. Look again, fries are 2.

STANDARD calculator: 5+2x10=

SCIENTIFIC calculator: 5+2x10=

#14
10-11-17, 07:02 AM
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Forgot this...

The Order of Operations: PEMDAS | Purplemath

I was up half the night on this. If it was 5+(2x10)= I would
have nailed it.

#15
10-11-17, 07:03 AM
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Baldwin, there are 4 fries on the 3rd line. Fries are 1.

#16
10-11-17, 07:21 AM
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You're right, didn't notice that.

Back to school for me.

#17
10-11-17, 02:57 PM
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T_G...it will probably come back with a whole page or 2 of calculations and proofs if he was taught the stuff I've seen being taught. I seriously don't get the NEW new math.

I told you...I don't do math normally. Between HS math, algebra, geometry, and trig...then more different formula's in Navy electronics schools, then even more math and chemistry (lot's of math in nuclear chemistry), and vector analysis....it just all kinda grew together....lol.

Problem is I can't figure out how to use a roofing square. Jeeze, I just wanted to figure a slope for my shed. Couldn't do it, wound up a 45 degree. Kinda tough to shingle, but great for snow and it never leaked when it rained. Had to buy one stair stringer for my deck, so I could trace it onto raw lumber for the rest.

But ask me what a 22.5% tip on a \$33 bill would be and I can do it pretty quick in my head and be accurate within about \$.02. I mean crap...why do I need to know what a "mole" is...but I do, just in case I ever need it.

Last edited by Gunguy45; 10-11-17 at 03:18 PM.

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