Finding the Fourth Proportional to 1,380.98, 2,070.83 and 514.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380.98 : 2,070.83 = 514.69 : x
2. Step 2: Convert to fraction form
   1,380.98/2,070.83 = 514.69/x
3. Step 3: Cross multiply
   1,380.98x = 2,070.83 × 514.69
4. Step 4: Simplify right side
   1,380.98x = 1,065,831.60
5. Step 5: Solve for x
   x = 1,065,831.60/1,380.98
6. Step 6: Final answer
   x = 771.79