Finding the Fourth Proportional to 1,380.61, 1,905.21 and 751.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380.61 : 1,905.21 = 751.15 : x
2. Step 2: Convert to fraction form
   1,380.61/1,905.21 = 751.15/x
3. Step 3: Cross multiply
   1,380.61x = 1,905.21 × 751.15
4. Step 4: Simplify right side
   1,380.61x = 1,431,100.87
5. Step 5: Solve for x
   x = 1,431,100.87/1,380.61
6. Step 6: Final answer
   x = 1,036.57