Answer:Company Z provides electricity for 8 houses.
Step-by-step explanation:
The total number of houses in the neighborhood is 40.
Company X provides electricity to 1/5 of the houses. This means that the number of houses that Company X provides for would be
1/5 × 40 = 8
Company Y provides electricity to 3/5 of the houses. This means that the number of houses that Company Y provides for would be
3/5 × 40 = 24
Company Z provides electricity to the remaining houses. Therefore,
the number of houses that Company Z provides for would be
40 - ( 8 + 24) = 40 - 32 = 8