Nfer maths 11A Q47.
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Nfer maths 11A Q47.
Can anyone suggest a simple way of working teh question out. Mine is so long winded that I am sure it would take FAR too long in a test.
It's a pie chart of trees in a park
we know that 20% are beech
30% are Ash
8% are lime.
so 100 - 58 = 42% oak. (the missing information)
We also know 12 trees are lime
so 8% of total =12.
How many oak trees?
0.08 of total = 12
12/0.08 = x
once we have found x then we can go on to work out 42% of this.
The numbers are not easy to work with though and calcualtors aren't allowed. Am I missing something obvious.
My brain is just not functioning this week.
It's a pie chart of trees in a park
we know that 20% are beech
30% are Ash
8% are lime.
so 100 - 58 = 42% oak. (the missing information)
We also know 12 trees are lime
so 8% of total =12.
How many oak trees?
0.08 of total = 12
12/0.08 = x
once we have found x then we can go on to work out 42% of this.
The numbers are not easy to work with though and calcualtors aren't allowed. Am I missing something obvious.
My brain is just not functioning this week.
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Road Runner
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mel x
Hi guest55
What do you think is the quickest way to work out devisions particularly when big numbers
DD is ok when deviding by 2 4 8 etc as you can half but panics when its odd numbers. As an example she had to work out
504 devided by 9
I showed her my way
_56___
9/504
9's into 50 = 5 r5 then 9's into 54 = 6 so answer = 56
Is this the quickest way?
Mel
What do you think is the quickest way to work out devisions particularly when big numbers
DD is ok when deviding by 2 4 8 etc as you can half but panics when its odd numbers. As an example she had to work out
504 devided by 9
I showed her my way
_56___
9/504
9's into 50 = 5 r5 then 9's into 54 = 6 so answer = 56
Is this the quickest way?
Mel
Mel X,
Many teachers think that is not the best way to start learning division -
504 divided by 9 - estimate answer ... 500 divided by 10 - so about 50.
Has she understood chunking yet? My answer would depend how far she is is her 'preferred method'.
9 x 10 = 90
9 X 50 = 450
504 - 450 = 54
9 x 6 = 54 so the answer is 56.
When they use short division try to keep place value so say 9 into 500 ...
Many teachers think that is not the best way to start learning division -
504 divided by 9 - estimate answer ... 500 divided by 10 - so about 50.
Has she understood chunking yet? My answer would depend how far she is is her 'preferred method'.
9 x 10 = 90
9 X 50 = 450
504 - 450 = 54
9 x 6 = 54 so the answer is 56.
When they use short division try to keep place value so say 9 into 500 ...
Dear Guest55
Please close your eyes and put your hands over your ears.
Dear Mel
I teach My 11 plus childeren, the old fashioned way to divide, as you have laid out in your post. The understanding may not be the best, but it is by far the quickest method for the basic division required for the selection tests. As my children are proficient in their times tables [2 to 12 plus 13 and 15] divisions by these numbers are relatively easy.
They use this knowledge to divide: 9/504
If its 18s into 90, they take a good guess, then check their guess by multiplying back up.
I also teach the old fashioned way of multiplying.
I tell the children that although they can use my method for 11 plus, they must revert to their teachers methods for their numeracy lessons....
Patricia
Please close your eyes and put your hands over your ears.
Dear Mel
I teach My 11 plus childeren, the old fashioned way to divide, as you have laid out in your post. The understanding may not be the best, but it is by far the quickest method for the basic division required for the selection tests. As my children are proficient in their times tables [2 to 12 plus 13 and 15] divisions by these numbers are relatively easy.
They use this knowledge to divide: 9/504
If its 18s into 90, they take a good guess, then check their guess by multiplying back up.
I also teach the old fashioned way of multiplying.
I tell the children that although they can use my method for 11 plus, they must revert to their teachers methods for their numeracy lessons....
Patricia
