Finding the Third Proportional to 1,405.79 and 2,139.06

Step by Step Solution

1. Step 1: Write the proportion equation
   1,405.79 : 2,139.06 = 2,139.06 : x
2. Step 2: Convert to fraction form
   1,405.79/2,139.06 = 2,139.06/x
3. Step 3: Cross multiply
   1,405.79x = 2,139.06 × 2,139.06
4. Step 4: Simplify right side
   1,405.79x = 4,575,596.73
5. Step 5: Solve for x
   x = 4,575,596.73/1,405.79
6. Step 6: Final answer
   x = 3,254.82