Question:
The figure shows two stacks of identical plastic cups. There are 4 plastic cups in the shorter stack and 6 plastic cups in the taller stack.
The height of the shorter stack is 19 cm and the taller stack is 24 cm.
Francis wants to pack the plastic cups as a single stack into a box of height 80 cm tall. What is the most number of plastic cups he can pack into the box?

Solution:
