Finding the Fourth Proportional to 1,378.89, 1,902.87 and 757.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,378.89 : 1,902.87 = 757.89 : x
2. Step 2: Convert to fraction form
   1,378.89/1,902.87 = 757.89/x
3. Step 3: Cross multiply
   1,378.89x = 1,902.87 × 757.89
4. Step 4: Simplify right side
   1,378.89x = 1,442,166.14
5. Step 5: Solve for x
   x = 1,442,166.14/1,378.89
6. Step 6: Final answer
   x = 1,045.89