Finding the Third Proportional to 128,254.50 and 278,412

Step by Step Solution

1. Step 1: Write the proportion equation
   128,254.50 : 278,412 = 278,412 : x
2. Step 2: Convert to fraction form
   128,254.50/278,412 = 278,412/x
3. Step 3: Cross multiply
   128,254.50x = 278,412 × 278,412
4. Step 4: Simplify right side
   128,254.50x = 77,513,241,744
5. Step 5: Solve for x
   x = 77,513,241,744/128,254.50
6. Step 6: Final answer
   x = 604,370.54