Finding the Fourth Proportional to 2,997.78, 4,495.20 and 917.40

Step by Step Solution

1. Step 1: Write the proportion equation
   2,997.78 : 4,495.20 = 917.40 : x
2. Step 2: Convert to fraction form
   2,997.78/4,495.20 = 917.40/x
3. Step 3: Cross multiply
   2,997.78x = 4,495.20 × 917.40
4. Step 4: Simplify right side
   2,997.78x = 4,123,897.25
5. Step 5: Solve for x
   x = 4,123,897.25/2,997.78
6. Step 6: Final answer
   x = 1,375.65