Answer:
86.25  
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Answer:

Step-by-step explanation:
From the question we are told that
Arc of 30 cm
10% reduction after each swing
Generally sum of geometric sequence is given by the equation
     
Mathematically solving for total distance traveled we have
     
     
Therefore the total distance traveled  by the pendulum after 5 swings
     
 
        
             
        
        
        
Answer: 348.8 miles on 16 gallons of gas
Step-by-step explanation:
Make the following proportion:
 =
 = 
Since the car consumes gas at the same rate and only the amount of gas is changed, these two fractions must be equivalent. If the rate at which the car consumes gas changes, it would be different. 
Use basic algebraic skills and you should get 348.8 miles.
 
        
             
        
        
        
Answer:
  
Step-by-step explanation: