When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
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Mostly I have that one memorized. Otherwise, I decompose it into 5*8 + 2*8, which is 40 + 16.
@michael_w_busch @futurebird Yup, same. Alas, I don't have the full* table memorized these days, but I know enough to be dangerous and can 2-step my way to the answer.
* Did we all learn up to 12x12? That's how UK schools do/did it.
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When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
@futurebird 4*14, maybe?
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When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
@futurebird
Memorized, sure, but that particular product takes me a second to remember it. -
When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
ohk im happy with the poll result, im also one of those that have some basic math thingies memorized and not really do any math to figure it out... phew!
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When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
@futurebird I will admit to doing 7×7 in my head and then adding seven!
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@futurebird I did 7*7=49 then added 7, which means 1 less than 7+50 (because ending in 9), resulting in 56.
I did have the multiplication tables memorized in 3 & 4 grade, but I don't really much basic math on a daily basis, and if I do, I generally need to write it down so I can see it. I'm afraid that if I don't make a deliberate effort, I'll be innumerate.
28*2 or 50-14 probably.
Rote - instant recall - memorization of the entire table seems unnecessary to me… once the first half is in your head the rest is available quickly though doubling and adjacent addition/subtraction, but also, because human brains are very inconsistent at it. Personally, I think that flexibility of knowing how to connect relationships across categories and patterns is a huge part of learning to *think* mathematically.
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When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
@futurebird I would say I don’t have it memorized. With the explanation given, I’ll probably use the other math fact that I have 2**n memorized a bit. So 8**2 = 64 then 64-8 = 56.
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When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
@futurebird I know my squares, so I do 7*7 and then add 7.
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When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
@futurebird when I was little I hated math and did everything to get out of doing any math. So I memorized the times tables, which I guess must have seemed easier? Anyway I remember being able to recite the correct answer quickly when it was just numbers, but being stumped when it was a word problem with apples or whatever.
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When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
When I forget my timestables:
7 * 10 = 70.
10-8 = 2.
2 * 7 = 14.
70-14 = 56. -
When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
@futurebird 7×8 = 5×8 + 2×8 = (10×8)/2 + 2×8 = 80/2 + 8 + 8 = 40 + 16 = 56
easy
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When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
@futurebird I remember learning my times tables as a kid. I still have the desk that I learned them at
Some of that has faded - for some reason I always stumble over results in the 40-60 range. So for this one (7*8) I would probably guess 56 or thereabouts, then check my work knowing that 8 squared is 64.
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When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
@futurebird I think 56, then doubt myself and think 5,6,7,8. Yes. 56=7*8
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When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
@futurebird I used to remember almost the entire multiplication table when I was at school, but I forgot most of it shortly after the final exams. But I can calculate it as something like 7*8=14*4=28+28=40+16=56
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When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
i have the benefit of being required early in public school to memorize the 12 by 12 multiplication table
in retrospect, it has stood me in good stead uncountable (see what i did there) times
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When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
Not convinced I do it the same way every time. This time, I relied on having the value of 7-squared memorized then added another 7.
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When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
@futurebird I knkw 7x7=49 and I add another 7.
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When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
@futurebird oddly enough, it was exactly this multiplication that tripped me up in front of an entire classroom - for some reason my brain had slipped a notch and decided 8*7 was 63... which, given that i was one of the school's star mathematicians, was a little bit embarrassing
so i picked the 3rd option in honour of that, although i have obviously never forgotten that eight sevens are fifty-six since...
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When you need to multiply 7*8 do you simply have it memorized, or do you need to add, subtract or otherwise connect it to another math fact that you know better?
That is do you simply think "56" or are there more thoughts that lead to 56?
@futurebird For some odd reason I have managed to keep all of the x *x numbers (all the squares) up to 100 memorized lo these many years. So I just square 7, then add or subtract 7s as required.
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@futurebird I remember learning my times tables as a kid. I still have the desk that I learned them at
Some of that has faded - for some reason I always stumble over results in the 40-60 range. So for this one (7*8) I would probably guess 56 or thereabouts, then check my work knowing that 8 squared is 64.
@MichaelPorter @futurebird I liked the fact that the 9-bys were a palindrome: 18 81, 27 72, 36 63, 45 54.
