Please help with this question!

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Starwriter
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Joined: Tue Mar 02, 2021 5:00 pm

Please help with this question!

Post by Starwriter »

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?
KaB£H1s3
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Location: Trafford

Re: Please help with this question!

Post by KaB£H1s3 »

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.
hermanmunster
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Re: Please help with this question!

Post by hermanmunster »

I suppose could do it by drawing a line:

Freddie ----- 2----- Alfie ----- 1 ------ Harry ------- 5 -------- Tom
Starwriter
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Re: Please help with this question!

Post by Starwriter »

Is there any easy solution for 10 years old?
yoyo123
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Re: Please help with this question!

Post by yoyo123 »

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
Blitz
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Re: Please help with this question!

Post by Blitz »

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!!)
ToadMum
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Re: Please help with this question!

Post by ToadMum »

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!!)
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 8).
.
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JustOutside
Posts: 183
Joined: Wed Feb 27, 2019 2:52 pm

Re: Please help with this question!

Post by JustOutside »

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.
BabaPabz
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Re: Please help with this question!

Post by BabaPabz »

Starwriter wrote:Is there any easy solution for 10 years old?
This is effectively an introduction to inequalities. It is best explained using number lines. as suggested earlier.
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).
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