The Student Room Group

maths

48,360 / 3,100???
4,836 / 1,560 ???
anyone know how to make division easier???
(edited 8 years ago)
Oh darn, that's difficult. Don't know how you'll get answers from this forum.
calculators were invented for a reason
Reply 3
Original post by Rhia Winterfell
48,360 / 3,100???


with a calculator?
Original post by Rhia Winterfell
48,360 / 3,100???


I'm guessing that you've asked this because you've got an exercise that involves manually going through the long division algorithm. As others have pointed out, a calculator makes this easy; however, if you don't have a calculator how should this be approached?

You can either grind through the long division algorithm...or you can note that sometimes big long divisions sums can be made easier easier by chipping out pieces of the numbers bit by bit using the fact that (a x b)/(c x b) = a/c.


So for this sum observe that:

(a) Top and bottom are divisible by 10; so take them out. 48,360 / 3,100 = 4836 / 310.

(b) Top and bottom are now divisible by 2; take them out: 4836 / 310 = 2418 / 155

(c) Gets a bit harder now, but note that 155 is divisible by 5: 155 = 31 x 5. 2418 is not divisible by 5...so we can't take that out, but now use long division to see if 2418 is divisible by 31. It is; 4836 = 78 x 31. So we can now take out 31 from top and bottom: 2418 /155 = 78 / 5. A much easier sum to do!

What we've done here is to reduce a tedious long division to a bit of thought plus an easier long division - all the hard work is done in working out 2418 / 31.
Reply 5
Original post by Gregorius
I'm guessing that you've asked this because you've got an exercise that involves manually going through the long division algorithm. As others have pointed out, a calculator makes this easy; however, if you don't have a calculator how should this be approached?

You can either grind through the long division algorithm...or you can note that sometimes big long divisions sums can be made easier easier by chipping out pieces of the numbers bit by bit using the fact that (a x b)/(c x b) = a/c.


So for this sum observe that:

(a) Top and bottom are divisible by 10; so take them out. 48,360 / 3,100 = 4836 / 310.

(b) Top and bottom are now divisible by 2; take them out: 4836 / 310 = 2418 / 155

(c) Gets a bit harder now, but note that 155 is divisible by 5: 155 = 31 x 5. 2418 is not divisible by 5...so we can't take that out, but now use long division to see if 2418 is divisible by 31. It is; 4836 = 78 x 31. So we can now take out 31 from top and bottom: 2418 /155 = 78 / 5. A much easier sum to do!

What we've done here is to reduce a tedious long division to a bit of thought plus an easier long division - all the hard work is done in working out 2418 / 31.


Or you can find highest common factor with Euclidean algorithm
edit: I dunno if this is much faster than long division since I don't think I've ever done long division on numbers lol
Double edit: well since the answer has a nice decimal the cheapest and quickest way is just normal non-calculator division
(edited 8 years ago)
Original post by Gregorius
I'm guessing that you've asked this because you've got an exercise that involves manually going through the long division algorithm. As others have pointed out, a calculator makes this easy; however, if you don't have a calculator how should this be approached?

You can either grind through the long division algorithm...or you can note that sometimes big long divisions sums can be made easier easier by chipping out pieces of the numbers bit by bit using the fact that (a x b)/(c x b) = a/c.


So for this sum observe that:

(a) Top and bottom are divisible by 10; so take them out. 48,360 / 3,100 = 4836 / 310.

(b) Top and bottom are now divisible by 2; take them out: 4836 / 310 = 2418 / 155

(c) Gets a bit harder now, but note that 155 is divisible by 5: 155 = 31 x 5. 2418 is not divisible by 5...so we can't take that out, but now use long division to see if 2418 is divisible by 31. It is; 4836 = 78 x 31. So we can now take out 31 from top and bottom: 2418 /155 = 78 / 5. A much easier sum to do!

What we've done here is to reduce a tedious long division to a bit of thought plus an easier long division - all the hard work is done in working out 2418 / 31.

hi, yeah i cant use a calculator, im useless at maths and even worse at long division
Original post by Rhia Winterfell
hi, yeah i cant use a calculator, im useless at maths and even worse at long division


Well, these boards are here to help! I can see from your user profile and previous posts that you're doing an access course for midwifery and that you're preparing for GCSE maths. So I hope that you're being supported by wherever you're studying at the moment in developing maths skills. My own university department offers courses in nursing and midwifery, and we're used to students arriving who have little previous experience of maths or who have forgotten what they once learned; we have special skills development workshops for such students.

You say you cant use a calculator - is this because you have never yet used one, or is there some reason you are unable to use one?
Original post by Gregorius
Well, these boards are here to help! I can see from your user profile and previous posts that you're doing an access course for midwifery and that you're preparing for GCSE maths. So I hope that you're being supported by wherever you're studying at the moment in developing maths skills. My own university department offers courses in nursing and midwifery, and we're used to students arriving who have little previous experience of maths or who have forgotten what they once learned; we have special skills development workshops for such students.

You say you cant use a calculator - is this because you have never yet used one, or is there some reason you are unable to use one?


im doing a maths assessment as part of my access course. im doing revision questions and some things i cant get my head around

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