Finding the Fourth Proportional to 1,359.76, 2,038.82 and 921.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,359.76 : 2,038.82 = 921.55 : x
2. Step 2: Convert to fraction form
   1,359.76/2,038.82 = 921.55/x
3. Step 3: Cross multiply
   1,359.76x = 2,038.82 × 921.55
4. Step 4: Simplify right side
   1,359.76x = 1,878,864.38
5. Step 5: Solve for x
   x = 1,878,864.38/1,359.76
6. Step 6: Final answer
   x = 1,381.77