Ava made juice out of oranges, apples, and pears. Oranges and apples are in the ratio 2:3, and apples and pears are in the ratio 2:5. What is the ratio of oranges to apples to pears in her juice?
                            
                         
                        
                            
                        
                             
                            
                            
                            
                                Explanation
                            
                                
                                    Answer: C - The ratio of oranges to apples to pears in a juice was 4:6:15. Denote oranges, apples and pears with x, y and z, respectively.
x:y = 2:3
y:z = 2:5
Look at the values for y in both proportions and find the least common multiple. The least common multiple for 3 and 2 is 6. Multiply the first proportion by 2, and the second proportion by 3.
x:y = 2:3⟺x:y = 4:6
y:z = 2:5⇔y:z = 6:15
x:y:z = 4:6:15
Therefore, the ratio of oranges to apples to pears is 4:6:15.