# A level maths linear interpolation HELP

Questions below =
(edited 1 month ago)
For 2ci, 8.2 is 0.2 above the starting point of the interval, and the class width is 0.5 so the ratio of people in there is 0.2/0.5
since there are 10 frequency in that interval, you do 0.2/0.5 x10 = 4, and add the 4 from the next interval which gets 8.

For 3c, I got the same UQ you got - not sure if the ms is wrong.

For 3d, since the qualifying time is 7.5 mins and its a competition about crossword puzzle i.e. taking longer means doing worse in the competition, then everyone who takes less than 7.5 mins is entered

For your logic if everyone who takes above 7.5 mins qualifies, you could take a thousand years to do the crossword and youd still get in the next round.

You did the right calculation just for the wrong interval.
Original post by mosaurlodon
For 2ci, 8.2 is 0.2 above the starting point of the interval, and the class width is 0.5 so the ratio of people in there is 0.2/0.5
since there are 10 frequency in that interval, you do 0.2/0.5 x10 = 4, and add the 4 from the next interval which gets 8.
For 3c, I got the same UQ you got - not sure if the ms is wrong.
For 3d, since the qualifying time is 7.5 mins and its a competition about crossword puzzle i.e. taking longer means doing worse in the competition, then everyone who takes less than 7.5 mins is entered
For your logic if everyone who takes above 7.5 mins qualifies, you could take a thousand years to do the crossword and youd still get in the next round.
You did the right calculation just for the wrong interval.

Sorry for bothering you but i still don't understand 2ci, qs is asking for how many earthworms are longer than 8.2cm, so that's 0.3/0.5 times 10 which is 6, add 4 which is 10. Where am I going wrong?
Oh yeah sorry I actually rushed that q - upon double checking my method you should be right - I was just trying to get my answer to match the markscheme.

Do you mind posting what the markscheme did for 2ci and 3c not sure what they did to get that - I recognise you are using the edexcel alevel book so you can just search "worked solutions [insert name of book]" and go to the relevant chapter and the answers should pop up.
(edited 1 month ago)
Original post by mosaurlodon
Oh yeah sorry I actually rushed that q - upon double checking my method you should be right - I was just trying to get my answer to match the markscheme.
Do you mind posting what the markscheme did for 2ci and 3c not sure what they did to get that - I recognise you are using the edexcel alevel book so you can just search "worked solutions [insert name of book]" and go to the relevant chapter and the answers should pop up.
Yh that's fine =

Original post by Hellooo123456

Not sure if you know but if you search up “PMT solution banks” you can find worked solutions for the questions instead of just ans