# percentage difference in practical

Watch
Announcements
#1
question 1 (b) where it talks about the percentage diiference I am just wondering what expression to use when calculating the percentage difference for n number of paper clips which im assuming is derived fron L= nc - 2d (n-1).

the mark scheme mentions about the expression to use for calculating percentage difference - 100 x ( 2d/c - 2d/nc) not sure how they achieved that?

Posted from TSR Mobile
0
6 years ago
#2
Off the top of my head the most logical way of thinking about it would be this:

The student suggests that , thus

represents the percentage, i.e, if and , nc is 120% L. I'm assuming that , as from the equation, L is equal to nc minus some value.

From the equation:

Converting this into a percentage as before:

From this it is clear that is the percentage difference.

If this isn't clear to you, if the percentage difference was 0, then we would have , or

The percentage difference being 0 infers

Remember as you posted, to avoid any confusion.
0
#3
(Original post by Phichi)
Off the top of my head the most logical way of thinking about it would be this:

The student suggests that , thus

represents the percentage, i.e, if and , nc is 120% L. I'm assuming that , as from the equation, L is equal to nc minus some value.

From the equation:

Converting this into a percentage as before:

From this it is clear that is the percentage difference.

If this isn't clear to you, if the percentage difference was 0, then we would have , or

The percentage difference being 0 infers

Remember as you posted, to avoid any confusion.
That makes sense, thanks a lot for your help
0
X

new posts
Back
to top
Latest
My Feed

### Oops, nobody has postedin the last few hours.

Why not re-start the conversation?

see more

### See more of what you like onThe Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

### Poll

Join the discussion

#### Poll: What factors affect your mental health most right now? Post-lockdown edition

5.68%
Uncertainty around my education (59)
11.55%
Uncertainty around my future career prospects (61)
11.94%
Lack of purpose or motivation (66)
12.92%
Lack of support system (eg. teachers, counsellors, delays in care) (28)
5.48%
Impact lockdown had on physical health (23)
4.5%
Social worries (incl. loneliness/making friends) (53)
10.37%
Financial worries (31)
6.07%
Concern about myself or my loves ones getting/having been ill (20)
3.91%
Exposure to negative news/social media (32)
6.26%
Difficulty accessing real life entertainment (15)
2.94%
Lack of confidence in making big life decisions (51)
9.98%
Worry about missed opportunities during the pandemic (43)
8.41%