Just seeking a little help with one of my daughter's Yr6 math questions, as the answer I get on a calculator is different from what she (and I) get by doing it the long division way.
The question is 2912 ÷ 52
Now by calculator it's 56, but by the long division way (admittedly I'm a little rusty on the method nowadays) I come up with 57 r48, which is completely wrong but I can't figure out why, yet when I simply work out 52 x 56 I get 2912.
I'm assuming I'm missing something, but not having needed to work out long division in my head since I left school, I'm (embarrassingly) not proving to be much use so any help would be grateful.
Thanks in advance.
I will explain a possible explanation to the problem, so you can check your work by using many possible methods of division. Here's how I'd solve it: 100 × 4 = 400. So, since 25 × 4 = 100, we can assume that $25\times 4\times 4 = 400$, where $4\times 4 = 16$, from your basic times tables. So, we can say that 25\times 16 = 400. Now that we've gotten 400 into groups of 25, now we can add the extra $400 + 25 = 425$, and $25 × 1 = 25$, so $25 × (16 + 1) = 25 × 17$. So, now, we have the fact family $25 × 17 = 425$, and, since division is backwards multiplication, we can switch around the fact family to then get $425 ÷ 25 = 17$, and this is our final answer.
And now, allow me to answer your question about the problem $2,912 ÷ 57$. Yet again, we only have to find the fact family. You already solved the crucial multiplication part, which is $52\times 56=2912$. Then, we take that, and we reverse it to make $2,912 ÷ 52=56$, the answer you wanted to know in the first place.
Hopefully this was helpful in answering your question, and I hope you can now get a right answer, regardless of disagreement from your calculations and the calculator's calculations.