Answer:
She will hire EZ Excavation.
Explanation:
For a company EZ Excavation,
Per cubic yards cost of the dirt =

=

= $24.5
Total cost of 40 cubic yards of the dirt = 40 × 24.5
= $980
For second company Happy Hauling service,
Per cubic yard cost of the dirt =

= $25
Cost of 40 cubic yards of the dirt = 40 × 25
= $1000
Budget of the contractor = $1000
Cost of dirt offered by EZ Excavation is in her budget and she is saving $20.
Therefore, she will hire EZ Excavation.