Finding the Third Proportional to 405,378 and 635,905.50

Step by Step Solution

1. Step 1: Write the proportion equation
   405,378 : 635,905.50 = 635,905.50 : x
2. Step 2: Convert to fraction form
   405,378/635,905.50 = 635,905.50/x
3. Step 3: Cross multiply
   405,378x = 635,905.50 × 635,905.50
4. Step 4: Simplify right side
   405,378x = 404,375,804,930.25
5. Step 5: Solve for x
   x = 404,375,804,930.25/405,378
6. Step 6: Final answer
   x = 997,527.75