Woody

Answer 2 : 100

a<b<c<d<e the 5 lengths
Asume c=d=e=140

(140-124)*3 = 48

To get the mean equal to 124 you need max(a)=b=124-48/2=100

...

Thanks for the response. But why does A=B?

When I tried to work this question out, I did A + 140 + 140 + 140 + E = 620 therefore A + E = 200. But I couldn't put a limit to A or E...

Thanks in advance

Other explanation :
In order to maximize A you need to have the smallest standard deviation for your list of numbers. So you get the mean equal to :
Mean = [max(A+B)+min(C+D+E)]/5
min(C+D+E)= 140+140+140 'cause E>=D>=C=140 (so you choose E=D=C=140)

A=B 'cause you want to maximize A (as B>=A, to maximize A you need A=B)
So max(A+B)=2A

Thus (2A+140*3)/5=124
Do the math and you get A=100

I don't know if it's clear, that's how it work in my head lol