Finding the Fourth Proportional to 1,510.14, 2,261.52 and 861.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,510.14 : 2,261.52 = 861.30 : x
2. Step 2: Convert to fraction form
   1,510.14/2,261.52 = 861.30/x
3. Step 3: Cross multiply
   1,510.14x = 2,261.52 × 861.30
4. Step 4: Simplify right side
   1,510.14x = 1,947,847.18
5. Step 5: Solve for x
   x = 1,947,847.18/1,510.14
6. Step 6: Final answer
   x = 1,289.85