Finding the Third Proportional to 7,809 and 12,490

Step by Step Solution

1. Step 1: Write the proportion equation
   7,809 : 12,490 = 12,490 : x
2. Step 2: Convert to fraction form
   7,809/12,490 = 12,490/x
3. Step 3: Cross multiply
   7,809x = 12,490 × 12,490
4. Step 4: Simplify right side
   7,809x = 156,000,100
5. Step 5: Solve for x
   x = 156,000,100/7,809
6. Step 6: Final answer
   x = 19,976.96