Finding the Third Proportional to 12,000 and 21,280

Step by Step Solution

1. Step 1: Write the proportion equation
   12,000 : 21,280 = 21,280 : x
2. Step 2: Convert to fraction form
   12,000/21,280 = 21,280/x
3. Step 3: Cross multiply
   12,000x = 21,280 × 21,280
4. Step 4: Simplify right side
   12,000x = 452,838,400
5. Step 5: Solve for x
   x = 452,838,400/12,000
6. Step 6: Final answer
   x = 37,736.53