Finding the Third Proportional to 259,276 and 388,918.50

Step by Step Solution

1. Step 1: Write the proportion equation
   259,276 : 388,918.50 = 388,918.50 : x
2. Step 2: Convert to fraction form
   259,276/388,918.50 = 388,918.50/x
3. Step 3: Cross multiply
   259,276x = 388,918.50 × 388,918.50
4. Step 4: Simplify right side
   259,276x = 151,257,599,642.25
5. Step 5: Solve for x
   x = 151,257,599,642.25/259,276
6. Step 6: Final answer
   x = 583,384.50