Answer:
20%
Explanation:
Number of phone calls received second month = 4265 + 25% of 4265
 = 4265 + 0.25 * 4265
 = 4265 ( 1 + 0.25)
 = 4265 * 1.25
 = 5331.25
Number of calls in third month = 6396
Increased calls than second month = 6396 - 5331.25
 = 1034.75

 
