A grocery store sells a bag of 6 oranges for $3.60. If Jeriel spent $2.40 on oranges, how many did he buy?

The cost of each orange is $3.60/6 = $<<3.60/6=0.60>>0.60.

If he spent $2.40, then he bought $2.40/$0.60 = <<2.40/0.60=4>>4 oranges. Answer: \boxed{4}.