#### Answer

Approximately 18,000 chicks were identified.
Exactly 18,000 chicks were identified.

#### Work Step by Step

To find the total number of chicks identified you must find the total number identified in the morning and the total number identified in the afternoon and then sum the two.
First, estimate the number of chicks identified using front end rounding.
In the morning, 48 chicks per minute were identified for a period of 4 hours. Determine how many minutes are in 4 hours.
$4 \times 60 = 240 $ minutes
$240 \approx 200$ minutes
Approximate the number of chicks identified per minute.
$48 \approx 50$
Multiply the number of minutes by the number of chicks per minute to find the approximate number identified in the morning.
$200 \times 50 = 10,000$ chicks identified in the morning
In the afternoon, 36 chicks per minute were identified for a period of 3 hours. Determine how many minutes are in 3 hours.
$3 \times 60 = 180 $ minutes
$180 \approx 200$ minutes
Approximate the number of chicks identified per minute.
$36 \approx 40$
Multiply the number of minutes by the number of chicks per minute to find the approximate number identified in the afternoon.
$200 \times 40 = 8,000$ chicks identified in the afternoon
Sum the chicks identified during the morning and afternoon.
10000 + 8000= 18,000 chicks identified
Now find the exact number of chicks identified.
In the morning, 48 chicks per minute were identified for a period of 4 hours. Determine how many minutes are in 4 hours, then multiply the number of minutes by 48.
$4 \times 60 = 240 $ minutes
$240 \times 48 = 11,520$ chicks identified in the morning
In the afternoon, 36 chicks per minute were identified for a period of 3 hours. Determine how many minutes are in 3 hours, then multiply the number of minutes by 36.
$3 \times 60 = 180 $ minutes
$180 \times 36 = 6,480$ chicks identified in the afternoon
Sum the chicks identified during the morning and afternoon.
11520 + 6480 = 18,000 chicks identified