Calling all Maths teachers, need tour help with homework question

[forago]

my child is doing some summer holiday maths set by his maths teacher. The question is:

32.45 x ? = 253.11

What is ?

obviously the answer is 7.8 and I think the question wants him to show that to work it out you do 253.11/32.45 which is the same as 25311/3245 so I am telling him to do 25311 divided by 3245 as a pretty convoluted long division to get 7.8, which is confusing him.

Am I over-complicating it? is there an easier way? what is the teacher after do you think?

Your long division method looks right, but I do it by writing my 3245 times table down the left hand side, and then just using that to work out how many 3245s there are in 25311 and what I need to subtract.

thanks! I'm sure I never did any of this at school ......

Looks like a standard question on inverse operations that would have been on a calculator paper - things like Year 6 SATs used to have a calculator paper, and some children would have been using them earlier, so my guess is that it might be a paper from a few years ago - some kind of prep for a scholarship or a practice book for SATs or something from that time, when calculator use was more standard at that age.

A surprising number of pupils find that sort of question quite difficult (even with a calculator) - just being able to work out which operation they need to do.

It does seem pointless to set it as a long division question.

I was about to post the same as Runaway. It looks like a calculator paper question (only worth 1 mark) checking that the children understand the inverse. I imagine it has accidentally found it's way in there. Hope so!

that makes a lot more sense now thanks, I think it must be a calculator one left over from somewhere as you say, he has just left the answer as the inverse and not worked it out. phew! thanks all for your help.

Part of what we were taught at my prep school, to get us through the 11+, were tricks exactly like those in ProudAs's post.

Another trick was to learn the alphabet backwards so you can say Z back to A, as quickly as you can A to Z. Helps in the "what's next in the sequence" questions. Seconds count!

We were also coached on the sort of trick questions to look out for ("what was the biggest island in the Pacific before Australia was discovered?" eg). We did at least one paper a week for what felt like years. I passed, unsurprisingly. My brother, who went to the boys' school, had no such help, and had never seen a paper, let alone had a go at one, failed. Some years later, his IQ was measured at 145.

So it really is down to coaching and practise.

I agree with the other posters that it must be a calculator question. I would never have set dd such a question to do without a calculator, unless I was trying to crush her enthusiasm for the subject.

I do, however, like Proud's method. Very clever. But I don't think it's what they are supposed to be doing at this age.

Pretty sure they are not indi entrance questions, but from a year 6 Sats paper. The pencil pointing to the answer box is Sats style. This will be from the Sats calculator paper.

A quick google reveals that all the questions shown are from the 2002 Sats level 3 -5 paper B (calculator allowed).