Finding the Third Proportional to 138,672 and 298,090

Step by Step Solution

1. Step 1: Write the proportion equation
   138,672 : 298,090 = 298,090 : x
2. Step 2: Convert to fraction form
   138,672/298,090 = 298,090/x
3. Step 3: Cross multiply
   138,672x = 298,090 × 298,090
4. Step 4: Simplify right side
   138,672x = 88,857,648,100
5. Step 5: Solve for x
   x = 88,857,648,100/138,672
6. Step 6: Final answer
   x = 640,775.70