Given

Anderson         :  Benjamin      :           Caleb             

 3                     :           1          :           3/2= 1.5     multiply by 2 for all ratio gives

 6                     :           2          :           3

Total 6+2+3=11

Difference in Anderson and Caleb is 6-3 =3

Given total 99 sweets,

99 * 3/11= 27

Anderson has 27 more sweets than Caleb

A has 3 times  as much as B and 2 times as much as C. It suggests that A’s amount is a multiple of 3 and 2. So let’s use 6u as the number of sweets A has.  Then

A: 6u
B: 2u
C: 3u

So total of 11u = 99. Thus u = 9. Anderson has 3u = 3 x 9 = 27 more than Caleb.

@Prettyhomework: noticed you posted your own solution and asked if you are correct. Yes, you are!