More exercise, help please
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More exercise, help please
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Answer doesn't seem to match to my little brain.
Answer doesn't seem to match to my little brain.
Re: More exercise, help please
Correct answer is C
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- Posts: 73
- Joined: Sun Jan 20, 2013 11:22 am
Re: More exercise, help please
Thanks, how it works.
Re: More exercise, help please
DS said that substitution works. He used N=4 and only one of those responses worked.
Re: More exercise, help please
You have to do this step by step.
N is first divided by 4. That gives you N/4.
Then you add 1. That gives you N/4 + 1.
Then you have to multiply the whole lot by 2. That gives you 2 x (N/4 +1), which is 2N/4 + 2, which is N/2 + 2.
Think of it this way - 1/4 x 2 is 2/4, which is 1/2.
N is first divided by 4. That gives you N/4.
Then you add 1. That gives you N/4 + 1.
Then you have to multiply the whole lot by 2. That gives you 2 x (N/4 +1), which is 2N/4 + 2, which is N/2 + 2.
Think of it this way - 1/4 x 2 is 2/4, which is 1/2.
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- Posts: 73
- Joined: Sun Jan 20, 2013 11:22 am
Re: More exercise, help please
Sometimes starts from left to right regardless of add or multiply but sometimes it is in hierarchal order. Which one we can teach. At least brackets will not confuse them at this stage.
Re: More exercise, help please
Eh? Think it follows BODMAS always. What did you mean by "which to teach?"