Finding the Fourth Proportional to 1,435.74, 1,980.61 and 938.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,435.74 : 1,980.61 = 938.40 : x
2. Step 2: Convert to fraction form
   1,435.74/1,980.61 = 938.40/x
3. Step 3: Cross multiply
   1,435.74x = 1,980.61 × 938.40
4. Step 4: Simplify right side
   1,435.74x = 1,858,604.42
5. Step 5: Solve for x
   x = 1,858,604.42/1,435.74
6. Step 6: Final answer
   x = 1,294.53