Finding the Third Proportional to 257,974 and 390,855.50

Step by Step Solution

1. Step 1: Write the proportion equation
   257,974 : 390,855.50 = 390,855.50 : x
2. Step 2: Convert to fraction form
   257,974/390,855.50 = 390,855.50/x
3. Step 3: Cross multiply
   257,974x = 390,855.50 × 390,855.50
4. Step 4: Simplify right side
   257,974x = 152,768,021,880.25
5. Step 5: Solve for x
   x = 152,768,021,880.25/257,974
6. Step 6: Final answer
   x = 592,183.79