A) identify the gcf and lcm of 360 and 480 b) identify four other common factors c) identify four other common multiples

The GCF and LCM of 360  and 480 ( 1440 - LMC) ( 2 x 2 x 2 x 3 x 5 = 12- GCF) 
The common factors are 2,3,5,
I don't know the four common multiples though, sorry. Hope this can be some help though :)
common factors:
360 = 2 x 2 x 2 x 3 x 3 x 5
480 = 2 x 2 x 2 x3 x 5 
Multiples of 360 : 360, 720, 1080 , 1440 , 1880...
Multiples of 480: 480, 960 , 1440, 1920, 2400...

than do 23.50 times 18 and then divide your answer by 100 than you will get x.