Finding the Fourth Proportional to 1,411.68, 1,947.79 and 821.86

Step by Step Solution

1. Step 1: Write the proportion equation
   1,411.68 : 1,947.79 = 821.86 : x
2. Step 2: Convert to fraction form
   1,411.68/1,947.79 = 821.86/x
3. Step 3: Cross multiply
   1,411.68x = 1,947.79 × 821.86
4. Step 4: Simplify right side
   1,411.68x = 1,600,810.69
5. Step 5: Solve for x
   x = 1,600,810.69/1,411.68
6. Step 6: Final answer
   x = 1,133.98