Pranoy is at a pet store and sees three turtle tanks. Each tank holds a different volume (in Liters) of water and a different number of turtles. Tank A holds 108 L and 15 turtles. Tank B holds 84 L and 12 turtles. Tank C holds 156 L and 20 turtles. Order the tanks by volume per turtle from least to greatest. Set up equivalent ratios for each tank.
(Please help!!)

Luke started a weight-loss program. the first week, he lost x pounds. the second week, he lost pounds less than times the pounds he lost the first week. the third week, he lost 1 pound more than of the pounds he lost the first week. liam started a weight-loss program when luke did. the first week, he lost 1 pound less than times the pounds luke lost the first week. the second week, he lost 4 pounds less than times the pounds luke lost the first week. the third week, he lost pound more than times the pounds luke lost the first week.