Finding the Fourth Proportional to 808,978.32, 1,213,457.76 and 209,886.12

Step by Step Solution

1. Step 1: Write the proportion equation
   808,978.32 : 1,213,457.76 = 209,886.12 : x
2. Step 2: Convert to fraction form
   808,978.32/1,213,457.76 = 209,886.12/x
3. Step 3: Cross multiply
   808,978.32x = 1,213,457.76 × 209,886.12
4. Step 4: Simplify right side
   808,978.32x = 254,687,941,030.29
5. Step 5: Solve for x
   x = 254,687,941,030.29/808,978.32
6. Step 6: Final answer
   x = 314,826.66