Finding the Third Proportional to 380,117 and 816,390

Step by Step Solution

1. Step 1: Write the proportion equation
   380,117 : 816,390 = 816,390 : x
2. Step 2: Convert to fraction form
   380,117/816,390 = 816,390/x
3. Step 3: Cross multiply
   380,117x = 816,390 × 816,390
4. Step 4: Simplify right side
   380,117x = 666,492,632,100
5. Step 5: Solve for x
   x = 666,492,632,100/380,117
6. Step 6: Final answer
   x = 1,753,388.12