Finding the Third Proportional to 12,904 and 21,300

Step by Step Solution

1. Step 1: Write the proportion equation
   12,904 : 21,300 = 21,300 : x
2. Step 2: Convert to fraction form
   12,904/21,300 = 21,300/x
3. Step 3: Cross multiply
   12,904x = 21,300 × 21,300
4. Step 4: Simplify right side
   12,904x = 453,690,000
5. Step 5: Solve for x
   x = 453,690,000/12,904
6. Step 6: Final answer
   x = 35,158.87