calculate the cost of a conference call lasting from 7pm to 8:30pm

Question

Jane's mobile phone plan charges $0.05 per minute at daytime rates before 8pm and $0.03 per minutes at nighttime rates after 8pm. A conference call cost 1.5 times the normal rate. 

Answer 1

Break up the call into 2 time periods, 7-8 and 8-8:30.  

 

From 7-8 is 60 minutes at 0.05 per minute times 1.5 for conference equals 

 

60*.05*1.5 = 3*1.5 = $4.50 

 

From 8-8:30 is 30 minutes at 0.03 per minute times 1.5 for conference equals

 

30*.03*1.5 = 0.9*1.5 = $1.35 

 

The total cost is $4.50 + $1.35 = $5.85