Finding the Third Proportional to 900,219.50 and 1,266,128

Step by Step Solution

1. Step 1: Write the proportion equation
   900,219.50 : 1,266,128 = 1,266,128 : x
2. Step 2: Convert to fraction form
   900,219.50/1,266,128 = 1,266,128/x
3. Step 3: Cross multiply
   900,219.50x = 1,266,128 × 1,266,128
4. Step 4: Simplify right side
   900,219.50x = 1,603,080,112,384
5. Step 5: Solve for x
   x = 1,603,080,112,384/900,219.50
6. Step 6: Final answer
   x = 1,780,765.82