According to my mother she's never seen or heard of anyone multiplying the way I do. My sisters and brother both do it her way including my father.. I don't know where or how I started using this method but to me I've always done it. Which way is the right way?
The answers are all the same yet the problems are different.
Example
My way:[code]
33
x 42
----
126
+ 126
----
1386
[/code]
Her way:
[code]
1
33
x 42
----
66
+ 132
-----
1386
[/code]
I'm sorry, but I really don't get the way you multiply.
Me neither, lol.
I use my head, i haven't use paper in years
[QUOTE=mankind_me;22023475]I'm sorry, but I really don't get the way you multiply.[/QUOTE]
Here lets try another problem.
[code]
48
x 62
---
496
248
-----
2976
Eight times 2 is 16 put the 1 ontop of 6 Eight times 6 is 48 plus 1 is 49
Four times 2 is 8 Four times 6 is 24
add em together and you get 2976
[/code]
[QUOTE=PlamZ;22023500]I use my head, i haven't use paper in years[/QUOTE]
Your parents never taught you not to draw on your face?
Okay, I get it, but I really just multiply 33 by 2, then 33 by 4 and move that result one digit back, like in the second code part, and add them.
Eh, I've never really understood that long and drawn process.
I do as OP does
33 x 10
(30 x 10) = 300 + (3 x 10) = 330
That's how i do it. By rounding off.
[editline]05:42PM[/editline]
To 10's
[QUOTE=Ericsson;22023762]I do as OP does[/QUOTE]
I'm glad I'm not the only one that does it this way but for some reason I feel less unique. :(
[IMG]http://i50.tinypic.com/2dmgn7k.jpg[/IMG]
If it's too hard to understand, I'll cut it out:
- How many times does it take "8" to get to "1"? Impossible.
- How many times does it take "8" to get to "18"? 2 = 16 - Write 16 under
- 18 - 16 = 2 back = write 2
- Pull down the next number; 4: 24
- How many times does it take "8" to get to "24"? 3 = 24 - Write 24 under 24
- 24 - 24 = 0 back = write 0
- You're done
It's not that complex, but I suck at describing it :/
That's how I was brought up doing it.
[editline]05:56PM[/editline]
Everyone in my school gets taught that way.
Which way? :P
Eh, in year 5 my maths teacher taught us all that we should use Napier's Bones for multiplication. I was like wat 0_0
[QUOTE=Busymonkey;22023994][IMG]http://i50.tinypic.com/2dmgn7k.jpg[/IMG]
If it's too hard to understand, I'll cut it out:
- How many times does it take "8" to get to "1"? Impossible.
- How many times does it take "8" to get to "18"? 2 = 16 - Write 16 under
- 18 - 16 = 2 back = write 2
- Pull down the next number; 4: 24
- How many times does it take "8" to get to "24"? 3 = 24 - Write 24 under 24
- 24 - 24 = 0 back = write 0
- You're done
It's not that complex, but I suck at describing it :/[/QUOTE]
That's how I learned.
your way:
33*42 = (30+3)*42
33*42 = 3*42*10 + 3*42
your mother's way:
33*42 = 33*(40+2)
33*42 = 33*4*10 + 33*2
[editline]08:20PM[/editline]
you should have a baby with your mother, it'd multiply like this:
33*42 = (30+3)*(40+2)
33*42 = 30*40 + 30*2 + 3*40 + 3*2
[QUOTE=PlamZ;22023500]I use my head, i haven't use paper in years[/QUOTE]
[QUOTE=Jimmg;22024662]Err.. no.[/QUOTE]
Yes.
[code] 33
x 42
----
126
+ 126
----
1386[/code]
You calculate 3*42
then you calculate 3*42 again, except shifted to the left (it's implied that a zero is inserted in the empty spot (in a decimal system, that's multiplying it by 10))
then you add them together
so
33*42 = (30+3)*42
33*42 = 3*42 + 3*42*10
you just can't use your calculator
you're trying to do it like this:
3
*42
+3
*42
*10
the calculator does exactly what you're telling it to do, so it's calculating this:
(3*42+3)*42*10
when it should be calculating this:
3*42 + 3*42*10 = 126 + 1260 = 1386
I do.
[QUOTE=ThePuska;22024886]you just can't use your calculator
you're trying to do it like this:
3
*42
+3
*42
*10
the calculator does exactly what you're telling it to do, so it's calculating this:
(3*42+3)*42*10
when it should be calculating this:
3*42 + 3*42*10 = 126 + 1260 = 1386[/QUOTE]
Cool I get it now.
OP, that's basically how I was taught too, except they told us to multiply the top by the bottom in stead of from the top down... if that makes sense...
I know your the only one who spells Multiplies that way.
Thats the way i was taught
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