Sadie finished her math test in 16 minutes less than three times the amount her friend took.

Question

Their total time combined is 1 hour and 8 minute. 

Answer 1

X is time in minutes

 

X + 3X-16 = 68 <--- 1 hour 8 min = 68 min , because 1 hour = 60 min

 

 

4x - 16 = 68

 

4x = 84

 

x = 21

 

3(21) - 16 = 63 - 16 = 47

 

Sadie finished the test in 21 minutes

Friend finished the exam in 47 minutes.