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> I first remind myself of the strategy to do it, which is first I will do 60 x 60. Then it is 3600, then I add 2 x 60, 3720, and then there is 2 x 62 left, but I have to keep reminding myself occasionally what the last numbers were, that initial multiplication was 62 x 62, then I got 3720, and now I have to add 124... okay lets go 3820, 24 left, now 3844. Of course it is easier to remember as I am typing this, but in my head I have to keep reminding myself. And now I am not sure if I did a mistake so I go verify that on the calculator. I do multiplication in my head similarly, just strip out the words, the numbers just flickers through and operations happens by themselves and I'm done in a second or two when I'm not rusty. Now that I'm rusty I do it more like (60x60=3600, 2x2=4, 60x2=120, 3600 + 4 + 120 + 120 = 3844), without doing any words, I just did that in my head right now and I am 100% sure not a single word, just the steps, I do sometimes verbalize the numbers so what I wrote in those parentheses is the most verbal my process for mathing that out gets. Edit: Looking at that, I think it might be easier for someone to correct your thinking if you think in words, but thinking without words is way faster and way more creative since it removes the restriction of only thinking about concepts you have words for. Edit2: I think your verbalization there is a ritual for the concepts to get to you. For me all I need to do is see 62x62 and imagine I want to solve it and all those thoughts flow to me automatically, basically a shortcut instead of having a large verbal ritual to piece together the concepts. I never did math verbally the way it is taught, so I am not sure how people think that way, to me this was always automatically this way. |
Also this multiplying of two digit numbers I was never taught, I just came to a strategy that I explained with my thoughts. And I used to do these for fun as a kid. But I would only get faster than that if it was something I had memorized, but not numbers from scratch. And I had to constantly try to repeat numbers in my head that I had stored for addition down the road.
What is usually tougher top of my head and especially if I am tired at all, is something like 68 x 68. Then here first I have to decide whether I go from 60 x 60 or 70 x 70. Since it's that close to 70, I think 70 is more likely be easier. So I think okay 4900 - that's from memory right. Then I start to think what I have to take off from 4900 and what is 68 x 68 lacking compared to 70 x 70. So I will think that if I add 2 x 68, it will make it 68 x 70 and then I have 2 x 70 missing. So I need to deduct 140 and 136. So now at this point, this is much easier done in writing but here I frequently have to repeat numbers or redo some steps because I am not certain or I forget. But otherwise 4900 - 140, this comes easily instantly 4760 - maybe that's how it is for you with 62 x 62. And then now I take 100 off, it's 4660, and further 36 it would be 4624. Right now testing this in my head it took more than a minute because I wasn't sure whether I could just use the logic that I was thinking out of the box and I'm quite tired.
What if you were to have to do something more difficult e.g. 3 digits multiplication or 4?