In order to qualify for a girls' regional 1500 meter race, an athlete's personal best time for the season must be under the qualifying time of 5 minutes 42 second.
1. Write an equation that expresses 'd' as the difference of the athlete's personal best time 't' (in seconds) and the qualifying time (in seconds)
2.Make a table that gives the value of 'd' for 't' = 341.7, 343.8, 340.9 , and 342.7. Which make values of 't' in the table are under the qualifying time? How can you tell from the differences?

Question

In order to qualify for a girls' regional 1500 meter race, an athlete's personal best time for the season must be under the qualifying time of 5 minutes  42 second.
1. Write an equation that expresses 'd' as the difference of the athlete's personal best time 't' (in seconds)  and the qualifying time (in seconds) 
2.Make a table that gives the value of 'd' for 't' = 341.7, 343.8, 340.9 , and 342.7. Which make values of 't' in the table are under the qualifying time? How can you tell from the differences?

anonymous · Answer

5'42'' = 5*60 +42 = 342 seconds
1/ d = t - 342
2/  t         |          341.7       |        343.8      |        340.9
   -------|---------------|-------------|----------- 
     d        |           -0.3         |          1.8        |         -1.1
The negative values of d make t under the qualifying time.