Finding the Fourth Proportional to 1,375.76, 1,898.32 and 778.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,375.76 : 1,898.32 = 778.05 : x
2. Step 2: Convert to fraction form
   1,375.76/1,898.32 = 778.05/x
3. Step 3: Cross multiply
   1,375.76x = 1,898.32 × 778.05
4. Step 4: Simplify right side
   1,375.76x = 1,476,987.88
5. Step 5: Solve for x
   x = 1,476,987.88/1,375.76
6. Step 6: Final answer
   x = 1,073.58