Finding the Third Proportional to 395,578 and 612,139

Step by Step Solution

1. Step 1: Write the proportion equation
   395,578 : 612,139 = 612,139 : x
2. Step 2: Convert to fraction form
   395,578/612,139 = 612,139/x
3. Step 3: Cross multiply
   395,578x = 612,139 × 612,139
4. Step 4: Simplify right side
   395,578x = 374,714,155,321
5. Step 5: Solve for x
   x = 374,714,155,321/395,578
6. Step 6: Final answer
   x = 947,257.32