Answer: The oranges.
Step-by-step explanation: I'll set up my work below.
Mangoes: $[tex]49/7=7[/tex] =$7 per mango
Apples: $[tex]24/4=6[/tex]=$6 per apple
Oranges: $[tex]15/3=5[/tex]=$5 per orange
Given this, the cheapest fruit is the orange.
I hope this helps!! Pls mark brainliest :)