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1. Need clarifying
7 - 4 + 3 x 0 + 1

This question was posted on google+. Some people were posting the answer as 1, a majority as 4 and a few as 2.

I understand that 1 is incorrect because a certain rule is not being applied.

But I don't know whether the correct answer is 4 or 2.

I understand that multiplication is carried out before division in terms of operations.

So you get 7 - 4 + 0 + 1

At the next step however I always thought you would do the same for addition being applied first and then subtraction so in that case, it would be....

7 - 5 = 2

So.. is 2 correct or do you first apply subtraction and THEN addition to get 4?
2. Re: Need clarifying
What you're bemused over is you're viewing it as

The answer is 4. There are no parentheses, ergo, it's
3. Re: Need clarifying
so after doing the multiplication bit, you go back to applying operations left to right?
4. Re: Need clarifying
7 - 4 + 3 x 0 + 1

Do the multiplication first and consider addition and subtraction equally (i.e moving from left to right).
5. Re: Need clarifying
(Original post by raees)
7 - 4 + 3 x 0 + 1

This question was posted on google+. Some people were posting the answer as 1, a majority as 4 and a few as 2.

I understand that 1 is incorrect because a certain rule is not being applied.

But I don't know whether the correct answer is 4 or 2.

I understand that multiplication is carried out before division in terms of operations.

So you get 7 - 4 + 0 + 1

At the next step however I always thought you would do the same for addition being applied first and then subtraction so in that case, it would be....

7 - 5 = 2

So.. is 2 correct or do you first apply subtraction and THEN addition to get 4?
1. Brackets
2. Orders/Indice
3. Multiplication
5. Subtraction

7 - 4 + 3 * 0 + 1

First you multiply 3 by 0 ( 0 by 3 is the exact same )
Now you are left with

7 - 4 + 1

Following no. 4 is addition which gives

7 - 3 or 8 - 4
Either way the final answer is 4 !

Enjoyable but overused.
Last edited by Khallil; 15-07-2012 at 20:45. Reason: Wrote Q3 rather than 3.
6. Re: Need clarifying
Addition and subtraction are the same operation (as indeed are multiplication and division) so they operate as left to right
7. Re: Need clarifying
oh! ok I get it now, but what happens if its say 7 / 4 * 3 ?

would you do 7 / (4 *3) ?
8. Re: Need clarifying
(Original post by raees)
oh! ok I get it now, but what happens if its say 7 / 4 * 3 ?

would you do 7 / (4 *3) ?
You would do 7/4 then *3 (L->R).
9. Re: Need clarifying
(Original post by raees)
oh! ok I get it now, but what happens if its say 7 / 4 * 3 ?

would you do 7 / (4 *3) ?
No:
10. Re: Need clarifying
(Original post by Khallil)
...

Enjoyable but overused.
I love the 1+1+...+1x0 ones - there's always comments from people going something along the lines of, "omg i carnt beleeve these idiots, its 0 ffs!!1"
11. Re: Need clarifying
(Original post by raees)
7 - 4 + 3 x 0 + 1

This question was posted on google+. Some people were posting the answer as 1, a majority as 4 and a few as 2.

I understand that 1 is incorrect because a certain rule is not being applied.

But I don't know whether the correct answer is 4 or 2.

I understand that multiplication is carried out before division in terms of operations.

So you get 7 - 4 + 0 + 1

At the next step however I always thought you would do the same for addition being applied first and then subtraction so in that case, it would be....

7 - 5 = 2

So.. is 2 correct or do you first apply subtraction and THEN addition to get 4?
Where did this 5 come from?

7 - 4 + 1, if you have -4 +1 then you get -3; not -5

So either way the final answer is 4.

Like it has already been mentioned, you'd go in order anyway and substitution/addition are in the same line of priority.
12. Re: Need clarifying
(Original post by TheGrinningSkull)
Where did this 5 come from?

7 - 4 + 1, if you have -4 +1 then you get -3; not -5

So either way the final answer is 4.

Like it has already been mentioned, you'd go in order anyway and substitution/addition are in the same line of priority.
thank you!
13. Re: Need clarifying
(Original post by raees)
thank you!
No worries
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