Finding the Fourth Proportional to 1,142,817.76, 1,714,209.16 and 278,260.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,142,817.76 : 1,714,209.16 = 278,260.72 : x
2. Step 2: Convert to fraction form
   1,142,817.76/1,714,209.16 = 278,260.72/x
3. Step 3: Cross multiply
   1,142,817.76x = 1,714,209.16 × 278,260.72
4. Step 4: Simplify right side
   1,142,817.76x = 476,997,075,092.20
5. Step 5: Solve for x
   x = 476,997,075,092.20/1,142,817.76
6. Step 6: Final answer
   x = 417,386.82