Finding the Fourth Proportional to 1,389.41, 1,916.31 and 829.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,389.41 : 1,916.31 = 829.76 : x
2. Step 2: Convert to fraction form
   1,389.41/1,916.31 = 829.76/x
3. Step 3: Cross multiply
   1,389.41x = 1,916.31 × 829.76
4. Step 4: Simplify right side
   1,389.41x = 1,590,077.03
5. Step 5: Solve for x
   x = 1,590,077.03/1,389.41
6. Step 6: Final answer
   x = 1,144.42