#### Answer

Approximately 5,100,000

#### Work Step by Step

The number of enrolled students is $17,487,475$.
The percentage of students who used grants and scholarships is $29\%$
To get an estimate without using a calculator, we'll round the percentage to $30\%$ and the number of students to $17,000,000$.
Our estimate is:
$17,000,000*\frac{30}{100}=1,700,000*3=5,100,000$
Now, let's check our estimate with a calculator:
$17,487,475*\frac{29}{100}=5,071,368$
Our estimate was reasonable.