Ahhhhhh ..... prime factorisation where 2 and 5 are the only prime factors.
Takes me back to a grade 8 Honours class I once taught where we took recurring and terminating decimals to pieces. There's nothing those kids couldn't do ....
This is something I like so much about SAT prep (assuming you're doing SAT prep the way we're doing SAT prep, which is to learn how to do the problems as opposed to learning 'strategies').
Every time I take an SAT section, I discover 'glitches' in my algebra 1 knowledge. These aren't gaps, exactly (for passersby: we've talked about gaps a lot on the blog).
It's not that I don't 'know' the concepts and procedures covered by the test.
It's that I don't know - or see? - the implications of what I know.
"Glitches" feels like the right word for the phenomenon.
In any event, having this chance to de-glitch C. (& me) as much as I can is great.
Ahhhhhh ..... prime factorisation where 2 and 5 are the only prime factors.
ReplyDeleteTakes me back to a grade 8 Honours class I once taught where we took recurring and terminating decimals to pieces. There's nothing those kids couldn't do ....
14? (Because 50^7 = 5^7 * 10^7 = 5^7 * 5^7 * 2^7 = 5^14 * 2^7?)
ReplyDeleteI was happy about this problem because just a few months ago I would have been mystified and today I could 'see' how to do it....
ReplyDeleteAnswer is 14.
This is something I like so much about SAT prep (assuming you're doing SAT prep the way we're doing SAT prep, which is to learn how to do the problems as opposed to learning 'strategies').
ReplyDeleteEvery time I take an SAT section, I discover 'glitches' in my algebra 1 knowledge. These aren't gaps, exactly (for passersby: we've talked about gaps a lot on the blog).
It's not that I don't 'know' the concepts and procedures covered by the test.
It's that I don't know - or see? - the implications of what I know.
"Glitches" feels like the right word for the phenomenon.
In any event, having this chance to de-glitch C. (& me) as much as I can is great.
Oh yeah! I was just about to look for an SAT problem where the answer was trivial if you used prime factorization for one of my tutoring students.
ReplyDelete50^7 = (5*5*2)^7
= (5^7)(5^7)(2^7)
=(5^14)(2^7)
Good question.