let's call the red triangle R, and the blue triangle B.
big/small
2.5/1.75 = 1.43 (rounded)
1.6/1.12 = 1.43 (rounded)
<u>missing side:</u> 2.35 x 1.43 = 3.36
Fleury will swim 51 laps on the sixth day if this pattern continues.
It would be the third one