Finding the Third Proportional to 420,556.50 and 660,960

Step by Step Solution

1. Step 1: Write the proportion equation
   420,556.50 : 660,960 = 660,960 : x
2. Step 2: Convert to fraction form
   420,556.50/660,960 = 660,960/x
3. Step 3: Cross multiply
   420,556.50x = 660,960 × 660,960
4. Step 4: Simplify right side
   420,556.50x = 436,868,121,600
5. Step 5: Solve for x
   x = 436,868,121,600/420,556.50
6. Step 6: Final answer
   x = 1,038,785.80