Maths M1 Edexcel Help??

So on question 4, I have managed to resolve correctly and get the 2 formulae as:
Fr=0.8kmg-0.6mg
R=0.8mg-0.6kmg
F=uR, therefore I can say that Fr=0.8umg, and then sub that in to the first one to get it in terms of K, but the answer from that isn't correct. I can't work out what I am doing wrong??

Reply 1

Towcestermaths

8

Original post by TopCat12

So on question 4, I have managed to resolve correctly and get the 2 formulae as:
Fr=0.8kmg-0.6mg
R=0.8mg-0.6kmg
F=uR, therefore I can say that Fr=0.8umg, and then sub that in to the first one to get it in terms of K, but the answer from that isn't correct. I can't work out what I am doing wrong??

Fr=0.8umg - 0.6ukmg