Finding the Third Proportional to 12,840 and 19,926

Step by Step Solution

1. Step 1: Write the proportion equation
   12,840 : 19,926 = 19,926 : x
2. Step 2: Convert to fraction form
   12,840/19,926 = 19,926/x
3. Step 3: Cross multiply
   12,840x = 19,926 × 19,926
4. Step 4: Simplify right side
   12,840x = 397,045,476
5. Step 5: Solve for x
   x = 397,045,476/12,840
6. Step 6: Final answer
   x = 30,922.54