Finding the Fourth Proportional to 1,383.56, 1,908.99 and 824.20

Step by Step Solution

1. Step 1: Write the proportion equation
   1,383.56 : 1,908.99 = 824.20 : x
2. Step 2: Convert to fraction form
   1,383.56/1,908.99 = 824.20/x
3. Step 3: Cross multiply
   1,383.56x = 1,908.99 × 824.20
4. Step 4: Simplify right side
   1,383.56x = 1,573,392.47
5. Step 5: Solve for x
   x = 1,573,392.47/1,383.56
6. Step 6: Final answer
   x = 1,137.21