Finding the Fourth Proportional to 388,819, 536,570.22 and 209,971

Step by Step Solution

1. Step 1: Write the proportion equation
   388,819 : 536,570.22 = 209,971 : x
2. Step 2: Convert to fraction form
   388,819/536,570.22 = 209,971/x
3. Step 3: Cross multiply
   388,819x = 536,570.22 × 209,971
4. Step 4: Simplify right side
   388,819x = 112,664,185,663.62
5. Step 5: Solve for x
   x = 112,664,185,663.62/388,819
6. Step 6: Final answer
   x = 289,759.98