It is 512 because you have to multiple 64x8=512 you should have figure that out and add 512+2=514 do you get it now ?
1.Simplified each one
2/5 (both divided by 7) , 1/2 (divided by 21)
2.Make them into integer
(2/5 )*(2/2)=4/10 , (1/2)*(5/5)=5/10
Now the dominators are the same ,you can just compare the numerators. It is 4:5
I believe the answer to this30+5+.2+.04+.005