Finding the Fourth Proportional to 1,355.88, 1,870.16 and 1,310.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,355.88 : 1,870.16 = 1,310.72 : x
2. Step 2: Convert to fraction form
   1,355.88/1,870.16 = 1,310.72/x
3. Step 3: Cross multiply
   1,355.88x = 1,870.16 × 1,310.72
4. Step 4: Simplify right side
   1,355.88x = 2,451,256.12
5. Step 5: Solve for x
   x = 2,451,256.12/1,355.88
6. Step 6: Final answer
   x = 1,807.87