i really need your help.. my daughter has math homework that i can't figure out.. it got so bad i told her to call her dad but apparently he's more deficient at 3rd grade math skills than i am, and she all but yelled at him and sent him to sit in the dunce corner.. here's the question.. hopefully someone can help..
what multiplication fact can be found using the arrays for 2*9 and 5*9?
i came up with 10.. but drawing out both tables and seeing that 10 showed up in both..
MissMath
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isn't it 63? If I am reading your question correctly....
michellecarin
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that question makes no sense and I teach 3rd grade math. An array for 2*9 is
2*9=18 18/2=9 18/9=2 9*2=18
an array for 5*9
5*9=45 9*5=45 45/9=5 45/5=9
mathteach
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All multiples of 9 add up to 9
18 1+8=9 27 2+7=9 36 3+6=9
etc...that's not a multiplication fact, though
Or...all multiples of 9, reversed, are also multiples of 9
18, 81 27, 72 36, 63
Again, not a multiplication fact, though
irishgrl1017
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THat ? could be asked wrong. I am not sure of the answer and I teach!!! My motto is, if I cant figure it out...how are my kids supposed to!
xXxNovember08xXx
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Posted by mathteach
All multiples of 9 add up to 9
18 1+8=9 27 2+7=9 36 3+6=9
etc...that's not a multiplication fact, though
Or...all multiples of 9, reversed, are also multiples of 9
18, 81 27, 72 36, 63
Again, not a multiplication fact, though
and i woudl HOPE u woudl kno above anyone on here!
jessamyn78
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7 x 9
2 x 9 plus 5 x 9 is 7 x 9
jessamyn78
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arrays are more like pictures for the facts like
2 x 9 is
x x x x x x x x x x x x x x x x x x
lonal
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I'm thinking 9 times 7 but not sure and yes, I teach 3rd grade too.
I made the array for 2 x 9 and then I made the array for 5 x 9. i'm thinking if you move them together you can find 7 x 9 but I may be reading the question wrong. Please let us know the answer!!!
jessamyn78
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Posted by lonal
I'm thinking 9 times 7 but not sure and yes, I teach 3rd grade too.
I made the array for 2 x 9 and then I made the array for 5 x 9. i'm thinking if you move them together you can find 7 x 9 but I may be reading the question wrong. Please let us know the answer!!!
That was my response also. I also teach 3rd grade.
