Finding the Fourth Proportional to 1,375.60, 1,898.46 and 786.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,375.60 : 1,898.46 = 786.40 : x
2. Step 2: Convert to fraction form
   1,375.60/1,898.46 = 786.40/x
3. Step 3: Cross multiply
   1,375.60x = 1,898.46 × 786.40
4. Step 4: Simplify right side
   1,375.60x = 1,492,948.94
5. Step 5: Solve for x
   x = 1,492,948.94/1,375.60
6. Step 6: Final answer
   x = 1,085.31