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Maths homework problem, David eats half his sweets and then buys 16 more. He now has 36 how many did he have to start with?

40

pretty straightforward

Unless i am missing something

36-16=20*2=40

Hard for year 2 I'd say...

Not the maths (36-16) x 2, but working out what the maths is from the problem.

Can't you just explain the question?

i.e. 'you need to take 16 away from 36 to find out how many sweets there were before the 16 were added. Then you need to multiply that figure by two'

i would say not hard if you sit and break down the two sums for them ie 36-16 then 20 +20... hard to break out the two sums yourself though...

I can do it, shark but should a 6 year old?

Seems a bit hard for Year 2 to me.

Give them something physical to work it out with? (like sweets )

Difficult for Y2 imo.

I'd say quite tricky for year 2. Were they meant to be able to do it on their own, or with help? The actual parts to it aren't too hard but working out what you are meant to do is more so.

I think by talking through it, then yes. I don't think it is the answer they are worried about but starting to develop thinking patterns? Did they cover it in class - ie; how to think about solving such questions? If no, then probably a bit tough, but i would say good for developing problem solving skills (with your help)

Sounds very hard for year 2.

Seems pretty standard 2 part word problem for Y2

Seems ok to me- teaching them to work backwards.

It's a bit hard for Y2, but DS1 could easily have done it in Y2, DD wouldn't have a clue.

I would imagine it's a problem given to the more able DC.

the maths is quite easy but the verbal reasoning is pretty hard for year 2 i'd say, i would expect maybe top 10% of a yr2 class to 'get it' without help... (i'm not a teacher but have experience with this age) is it an extention activity?

DS is in yr 2 and it sounds like the sort of thing they include in the 'stretch' part of his numeracy homework...he'd be fine with it, but that's cos he absolutely loves playing with numbers - I don't think the majority of his class would be able to understand it without adult input.

Is your dc supposed to be doing their numeracy homework independantly or with help/supervision?

Ds1 is yr 4 and quite good at maths, but he didn't work it out.

So the other bits were all one part word problems, he had no idea to start with but he got it when I explained. I think it may have been an extension activity but am not sur

Ds (also yr2) sometimes gets questions like this which completely floor me

He can do it with some explanation. IE you now have 36 sweets, you need to take away 16 sweets because.....and then he could work the rest out himself iyswim.

mrz seriously??? No way would the vast majority of year 2 kids get that. Took me a while...

I think this is hard for yr2. That's the type of maths problem that would have left me and dd1 in tears because no matter how hard I tried, she just couldn't (wouldn't?) understand it.

Witchwith asked: 'David eats half his sweets and then buys 16 more. He now has 36 how many did he have to start with?'
A very good way to approach problems like this is to represent them in concrete terms. If you draw a bar line with 36 equal segments on it and then count and mark off sixteen of them, you can see very clearly that you have 20 left. This 20 is the half of the sweets that David had left. As long as the child you're working with understands that two halves make a whole, you can ask them to add the two halves together (20 + 20) to make 40. Or, you can represent it graphically, say, as a tin half full with twenty sweets in it and talk about how many you would have altogether if the tin was full.
However, if you want a quick answer for yourself, you let X represent the original number of sweets. Half this number is 1/2X (the number of sweets David had left). You then add 16 and this leaves a total of 36. As an equation, this is 1/2X + 16 = 36. Now subtract 16 from both sides of the equation and you are left with 1/2X = 20. If 1/2 X = 20, then X must equal 40.