Two numbers are 20% and 50% more than a third number. What is the ratio of these two numbers?

Problem restatement
Let the third number be t. Then the two numbers are 1.2t and 1.5t. Find their ratio.

Concept/Approach
Ratios scale out common factors: (1.2t : 1.5t) = (1.2 : 1.5).

Step-by-step calculation
1.2 : 1.5 = 12 : 15 = 4 : 5

Verification/Alternative
Pick t = 10 → numbers 12 and 15 → ratio 4 : 5.

Final Answer
4 : 5