Finding the Fourth Proportional to 1,381.10, 1,905.59 and 933.80

Step by Step Solution

1. Step 1: Write the proportion equation
   1,381.10 : 1,905.59 = 933.80 : x
2. Step 2: Convert to fraction form
   1,381.10/1,905.59 = 933.80/x
3. Step 3: Cross multiply
   1,381.10x = 1,905.59 × 933.80
4. Step 4: Simplify right side
   1,381.10x = 1,779,435.27
5. Step 5: Solve for x
   x = 1,779,435.27/1,381.10
6. Step 6: Final answer
   x = 1,288.42