Finding the Fourth Proportional to 1,380.84, 2,061.15 and 1,216.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,380.84 : 2,061.15 = 1,216.82 : x
2. Step 2: Convert to fraction form
   1,380.84/2,061.15 = 1,216.82/x
3. Step 3: Cross multiply
   1,380.84x = 2,061.15 × 1,216.82
4. Step 4: Simplify right side
   1,380.84x = 2,508,042.80
5. Step 5: Solve for x
   x = 2,508,042.80/1,380.84
6. Step 6: Final answer
   x = 1,816.32