### Home > CCA > Chapter 3 > Lesson 3.2.4 > Problem 3-72

If Harry and Heinrick start eating at the same time, when will their ponds have the same number of lily pads remaining?

Write an equation representing each hippo. Let

time (in hours) andthe number of lily pads. Note that the growth is negative.Harry's equation is

.Set the two equations equal to each other and solve for

. They will have eaten the same number of lily pads when the equations forare equal. hours

Don't forget to check your solution!How many lily pads will be left in each pond at that time?

Substitute

back into one of the original equations and solve for .