Answer
Estimate: $30,000$
Exact: $28,988$
Work Step by Step
We need to subtract:
$~~~75,078$
$-\underline{46,090}$
First, we estimate by rounding:
$~~~80,000$
$-\underline{50,000}$
$~~~30,000$
Next, we find the exact answer:
$~~~75,078$
$-\underline{46,090}$
$~~~28,988$
We see that our estimate and exact answers are fairly similar.