Finding the Fourth Proportional to 1,401.75, 1,934.42 and 780.75

Step by Step Solution

1. Step 1: Write the proportion equation
   1,401.75 : 1,934.42 = 780.75 : x
2. Step 2: Convert to fraction form
   1,401.75/1,934.42 = 780.75/x
3. Step 3: Cross multiply
   1,401.75x = 1,934.42 × 780.75
4. Step 4: Simplify right side
   1,401.75x = 1,510,294.51
5. Step 5: Solve for x
   x = 1,510,294.51/1,401.75
6. Step 6: Final answer
   x = 1,077.44