To determine how many glasses of liquid are in 5 liters when each glass holds 1/4 liter, you need to divide the total volume (5 liters) by the volume of one glass (1/4 liter).
This can be represented mathematically as:
\[ 5 \div \frac{1}{4} \]
This is equivalent to multiplying by the reciprocal of 1/4, which is 4:
\[ 5 \times 4 = 20 \]
Thus, the expression that represents the problem is:
5 divide by 1/4.