Answer:
Felipe = 23 messages
Keisha = 31 messages
Manuel = 46 messages
Step-by-step explanation:
Keisha = K
Felipe = F
Manuel = M
=> There are a total of 100 messages.
=> K sent 8 +F => K = 8 + F
=> M sent 2 * F => M = 2F
=> F = F
=> 8 + F + 2F + F = 100
=> 8 + 4F = 100
=> 8 - 8 +4F = 100 -8
=> 4F = 92
=> 4F/4 = 92/4
=> F = 23
So, Felipe = 23 messages.
   Keisha = 8 + F = 8 + 23 = 31 messages.
   Manuel = 2F = 2* 23 = 46 messages.
46 + 31 + 23 = 77 + 23 = 100 messages.
So, the answer is correct.
