Please help with this question!
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Please help with this question!
Tom weighs 5kg more than Harry. Harry weighs 3kg more than Freddie who. in turn weighs 2kg less than Alfie. What is the difference, in kilograms between Tom and Alfie?
Re: Please help with this question!
6kg?
Tom weighs 5kg more than Harry.
H+5=T
Harry weighs 3kg more than Freddie
H-3=F or H=F+3
who in turn weighs 2kg less than Alfie.
F+2=A
What is the difference, in kilograms between Tom and Alfie?
T-A=H+5-(F+2)
Then substitute H for F and finish it.
I think it's too hard for a 10 year old fwiw.
Tom weighs 5kg more than Harry.
H+5=T
Harry weighs 3kg more than Freddie
H-3=F or H=F+3
who in turn weighs 2kg less than Alfie.
F+2=A
What is the difference, in kilograms between Tom and Alfie?
T-A=H+5-(F+2)
Then substitute H for F and finish it.
I think it's too hard for a 10 year old fwiw.
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Re: Please help with this question!
I suppose could do it by drawing a line:
Freddie ----- 2----- Alfie ----- 1 ------ Harry ------- 5 -------- Tom
Freddie ----- 2----- Alfie ----- 1 ------ Harry ------- 5 -------- Tom
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Re: Please help with this question!
Is there any easy solution for 10 years old?
Re: Please help with this question!
Hermanmunster’s suggestion is a good one.
Drawing diagrams really helps with probkems lije this. In school children use white boards for rough working and diagram/pictorial representation is encouraged
Drawing diagrams really helps with probkems lije this. In school children use white boards for rough working and diagram/pictorial representation is encouraged
Re: Please help with this question!
If you give Alfie a nominal weight of, say, 10kg then work backwards, it is quite straightforward:
Alfie = 10kg
Freddie = Alfie -2 = 8kg
Harry = Freddie + 3 = 11kg
Tom = Harry + 5 = 16kg
So Tom - Alfie = 16 - 10 = 6kg
(At these weights the boys would be babies!!)
Alfie = 10kg
Freddie = Alfie -2 = 8kg
Harry = Freddie + 3 = 11kg
Tom = Harry + 5 = 16kg
So Tom - Alfie = 16 - 10 = 6kg
(At these weights the boys would be babies!!)
Re: Please help with this question!
DS2 was 19.3Kg at his weighing in Reception - I only remember that because I noted at the time that it was exactly 5 times his birth weight .Blitz wrote:If you give Alfie a nominal weight of, say, 10kg then work backwards, it is quite straightforward:
Alfie = 10kg
Freddie = Alfie -2 = 8kg
Harry = Freddie + 3 = 11kg
Tom = Harry + 5 = 16kg
So Tom - Alfie = 16 - 10 = 6kg
(At these weights the boys would be babies!!)
.
Outside of a dog, a book is a man's best friend. Inside of a dog it's too dark to read.Groucho Marx
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Re: Please help with this question!
I would do it as a vertical list.
So, Freddie weighs 2kg less than Alfie:
Alfie
-2
Freddie
Harry weighs 3kg more than Freddie, so Harry goes 1kg above Alfie:
Harry
-1
Alfie
-2
Freddie
Tom weighs 5kg more than Harry, so that can easily be fitted at the top:
Tom
-5
Harry
-1
Alfie
-2
Freddie
So, the difference between Tom and Alfie is 5+1=6, so 6kg.
So, Freddie weighs 2kg less than Alfie:
Alfie
-2
Freddie
Harry weighs 3kg more than Freddie, so Harry goes 1kg above Alfie:
Harry
-1
Alfie
-2
Freddie
Tom weighs 5kg more than Harry, so that can easily be fitted at the top:
Tom
-5
Harry
-1
Alfie
-2
Freddie
So, the difference between Tom and Alfie is 5+1=6, so 6kg.
Re: Please help with this question!
This is effectively an introduction to inequalities. It is best explained using number lines. as suggested earlier.Starwriter wrote:Is there any easy solution for 10 years old?
if you draw the child a line and location Tom, Harry and Freddie...it becomes fairly simple.
The real difficulty is to explain to the child that similar questions may require the equation treatment when it involves equality and the relationship are relative (multiple) rather than absolute (add/subtract).