Finding the Third Proportional to 387.56 and 805.50

Step by Step Solution

1. Step 1: Write the proportion equation
   387.56 : 805.50 = 805.50 : x
2. Step 2: Convert to fraction form
   387.56/805.50 = 805.50/x
3. Step 3: Cross multiply
   387.56x = 805.50 × 805.50
4. Step 4: Simplify right side
   387.56x = 648,830.25
5. Step 5: Solve for x
   x = 648,830.25/387.56
6. Step 6: Final answer
   x = 1,674.13