Finding the Fourth Proportional to 1,399.75, 1,931.69 and 770.29

Step by Step Solution

1. Step 1: Write the proportion equation
   1,399.75 : 1,931.69 = 770.29 : x
2. Step 2: Convert to fraction form
   1,399.75/1,931.69 = 770.29/x
3. Step 3: Cross multiply
   1,399.75x = 1,931.69 × 770.29
4. Step 4: Simplify right side
   1,399.75x = 1,487,969.45
5. Step 5: Solve for x
   x = 1,487,969.45/1,399.75
6. Step 6: Final answer
   x = 1,063.03