If the landlord pays 20% of the cost for both Liability and Contents insurance, and the total cost for both insurances is $45 per month when purchased together, then you need to calculate how much you have to pay after the landlord's contribution.
Let \( x \) be the cost of Liability insurance and \( y \) be the cost of Contents insurance.
Since the landlord pays 20% of the total cost, you pay 80% of the total cost.
So, the cost to you per month for both insurances is:
\[ 0.8 \times \$45 = \$36 \]
Therefore, if you buy both insurances and take advantage of the landlord's offer, the cost to you per month is $36.