Answer:
Mark these points on the graph:
(0,3)
(1,4)
(2,5)
(3,6)
(4,7)
(5,8)
(6,9)
(7,10)
Then draw a line on the points.
A little washer on wine cap
X+(x-5) +(x-10) ...
This adds up to 8x -140 seconds where x is the 1st race time.
This adds up to 44:20 minutes
44mins * 60 sec/min = 2640 seconds + 20 = 2660 seconds cummulative
8x - 140 = 2660 8x =2800 sec
8x = 350 seconds or 4.5mins for the 1st race
Race 2: subtract 5 seconds yields 4 mins 25 seconds