Anyone Good at Maths?

Secteur
Secteur Posts: 1,971
edited July 2012 in Road general
I am really, really bad with numbers (dyscalculia, actually!), so could someone help me.

What formula should I use to calculate an "average percentage grade" across my whole ride;

for example if I rode 50 miles and my garmin tells me I had 1200 metres of climbing (vertical ascent), what would that work out to if it were a linear slope the whole way?

Thanks :-)

Comments

  • BruceG
    BruceG Posts: 347
    1.5% so flatish
  • izza
    izza Posts: 1,561
    As Einstein proved, measurements of various quantities are relative to the velocities of observers. As such, what was your average speed?
  • 50 miles is about 80km, or 80000 meters. You went up 1200m.

    So 1200m of up in 80000 meters is 1200 ÷ 80000 * 100 = 1.5%

    Or 1 in 66 in old money.
  • Secteur
    Secteur Posts: 1,971
    That's great, thanks!
  • P_Tucker
    P_Tucker Posts: 1,878
    No-one on here it would seem. You need to remember to subtract the number of metres of descending.

    Top Tip - if you start and finish in the same place, the answer is always 0%.
  • sungod
    sungod Posts: 17,351
    ^^^this

    in which case you can calculate the average gradient climbing as...

    total height gained

    divided by

    half the total distance

    for the example you give, that'll be...

    1200 / 40000 (40000 m is about 25 miles)

    which is 0.03

    multiply by 100 to turn it into %, and you have 3%
    my bike - faster than god's and twice as shiny
  • Pedantically, he never said he did any descending or did a loop.
  • P_Tucker
    P_Tucker Posts: 1,878
    Pedantically, he never said he did any descending or did a loop.

    Pedantically:

    1. if he does no descending then he can subtract zero and it'll still work just fine.
    2. No-one said he did a loop. The key word here is "if".
    3. Why do you assume the OP is a "he"?
  • Secteur
    Secteur Posts: 1,971
    Oi! settle down at the back!

    Thanks for the help.

    And just for completeness, I am a he (the last time I checked, anyway), and it is a loop that I tend to ride.
  • bails87
    bails87 Posts: 12,998
    Well if it's a loop then the average gradient is zero, isn't it. Unless yo uget home and you're well above or below the road.
    MTB/CX

    "As I said last time, it won't happen again."
  • BruceG
    BruceG Posts: 347
    P_Tucker wrote:
    No-one on here it would seem. You need to remember to subtract the number of metres of descending.

    Top Tip - if you start and finish in the same place, the answer is always 0%.

    You need to read the OP, he asked as if it were a linear slope the whole way! thats the answer he got, so you accuse others of not being good at maths guess English isnt your forte!
  • P_Tucker
    P_Tucker Posts: 1,878
    BruceG wrote:
    P_Tucker wrote:
    No-one on here it would seem. You need to remember to subtract the number of metres of descending.

    Top Tip - if you start and finish in the same place, the answer is always 0%.

    You need to read the OP, he asked as if it were a linear slope the whole way! thats the answer he got, so you accuse others of not being good at maths guess English isnt your forte!

    I think what's happened here is that you've brainfarted.
  • BruceG
    BruceG Posts: 347
    P_Tucker wrote:
    BruceG wrote:
    P_Tucker wrote:
    No-one on here it would seem. You need to remember to subtract the number of metres of descending.
    B
    Top Tip - if you start and finish in the same place, the answer is always 0%.

    You need to read the OP, he asked as if it were a linear slope the whole way! thats the answer he got, so you accuse others of not being good at maths guess English isnt your forte!

    I think what's happened here is that you've brainfarted.

    Strange way of saying you wrong, but i guess further evidence of your lacking english skills
  • P_Tucker
    P_Tucker Posts: 1,878
    BruceG wrote:
    P_Tucker wrote:
    BruceG wrote:
    P_Tucker wrote:
    No-one on here it would seem. You need to remember to subtract the number of metres of descending.
    B
    Top Tip - if you start and finish in the same place, the answer is always 0%.

    You need to read the OP, he asked as if it were a linear slope the whole way! thats the answer he got, so you accuse others of not being good at maths guess English isnt your forte!

    I think what's happened here is that you've brainfarted.

    Strange way of saying you wrong, but i guess further evidence of your lacking english skills

    FFS. Right, lets help you out, as you appear to be struggling with both maths and English. If the OP did a ride which involved say 1000m of climbing and 900m of descending over 100km, then he will finish 100m higher than he started. With me so far? Now, as you point out, the OP requested a "linear slope the whole way". The whole way is 100km. He finished 100m higher than he started. If it helps, try to imagine drawing a straight line between the two. So we have 100 / 100000 * 100% = 0.1%.

    As it happens, sungod gave the best answer. The OP simply asked the wrong question.

    Another top tip - if you are going to mock someone for being wrong, try to make sure you're right.
  • BruceG
    BruceG Posts: 347
    P_Tucker wrote:
    BruceG wrote:
    P_Tucker wrote:
    BruceG wrote:
    P_Tucker wrote:
    No-one on here it would seem. You need to remember to subtract the number of metres of descending.
    B
    Top Tip - if you start and finish in the same place, the answer is always 0%.

    You need to read the OP, he asked as if it were a linear slope the whole way! thats the answer he got, so you accuse others of not being good at maths guess English isnt your forte!

    I think what's happened here is that you've brainfarted.

    Strange way of saying you wrong, but i guess further evidence of your lacking english skills

    FFS. Right, lets help you out, as you appear to be struggling with both maths and English. If the OP did a ride which involved say 1000m of climbing and 900m of descending over 100km, then he will finish 100m higher than he started. With me so far? Now, as you point out, the OP requested a "linear slope the whole way". The whole way is 100km. He finished 100m higher than he started. If it helps, try to imagine drawing a straight line between the two. So we have 100 / 100000 * 100% = 0.1%.

    As it happens, sungod gave the best answer. The OP simply asked the wrong question.

    Another top tip - if you are going to mock someone for being wrong, try to make sure you're right.

    Excatly right HE ASKED THE WRONG question, go back and read what he asked the answer he got from me and the others was correct for the question he asked FFS as you crudely put it, so to use your own advice dont mock others when you are WRONG

    PS I hear McDonalds are looking for a stand suit you down to the ground CLOWN
  • snowjho
    snowjho Posts: 108
    This is getting good... Maths with a capital M or not? As a Maths teacher I think it should even if grammatically its incorrect.
  • P_Tucker
    P_Tucker Posts: 1,878
    BruceG wrote:
    Excatly right HE ASKED THE WRONG question, go back and read what he asked the answer he got from me and the others was correct for the question he asked FFS as you crudely put it, so to use your own advice dont mock others when you are WRONG

    PS I hear McDonalds are looking for a stand suit you down to the ground CLOWN

    :lol: Since the OP didn't state the amount of descending he did on his hypothetical ride, the correct answer is "it depends on the amount of descending you did". Not doing a sum with incomplete information.

    You really are humiliating yourself, do try to stop.
  • Secteur
    Secteur Posts: 1,971
    Ok, please stop everyone!

    I probably wasn't too clear with my question - I was meaning what would the average grade of just the ascent be (discounting the descents) over the distance.

    I understand the maths better now, so I can do my calculations from here.

    Thanks again everyone (and please stop squabbling - I don't like it!)
  • Secteur wrote:
    Ok, please stop everyone!

    I probably wasn't too clear with my question - I was meaning what would the average grade of just the ascent be (discounting the descents) over the distance.

    I understand the maths better now, so I can do my calculations from here.

    Thanks again everyone (and please stop squabbling - I don't like it!)


    Just be thankful they're not questioning your manhood :wink:


    :lol:
  • izza
    izza Posts: 1,561

    Just be thankful they're not questioning your manhood :wink:

    :lol:

    Now that's a completely different mathematical formulae which centres upon the angle of dangle rather than the incline of the pass.
  • solosuperia
    solosuperia Posts: 333
    NO has to be the emphatic answer im my case.......

    I have a triangle of ground, no great size about 1.5 metres equilateral that I want to pave with bricks.
    So worked out the area (height*base)/2. I honestly can't remember the result, measured a brick did the maths divided one in to the other. Went and picked up 30 bricks because that was the answer I arrived at .

    Heavens knows where I went wrong I appear to have twice as many bricks as I need.....I haven't got round to laying them yet, so might be getting the wrong impression.

    DShould have learnt by now.... Always measure twice!