Answer:
84 days 
Step-by-step explanation:
You would use the LCM to solve this.
12 and 7 don't share any common factors other than 1, 
so you would multiply 12 x 7, which gets you 84.
After 84 days they would have raised the same amount.
  
        
             
        
        
        
Answer:
x=-3 and x=-7
Step-by-step explanation:
 
        
             
        
        
        
Answer:
3.75
Step-by-step explanation:
 
        
             
        
        
        
Find the LCM (least common multiple) of the denominators, and use that as the denominator for the two fractions.
Ex.

LCM (3, 4) is 12

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