Finding the Fourth Proportional to 1,381.47, 1,906.79 and 961.89

Step by Step Solution

1. Step 1: Write the proportion equation
   1,381.47 : 1,906.79 = 961.89 : x
2. Step 2: Convert to fraction form
   1,381.47/1,906.79 = 961.89/x
3. Step 3: Cross multiply
   1,381.47x = 1,906.79 × 961.89
4. Step 4: Simplify right side
   1,381.47x = 1,834,122.23
5. Step 5: Solve for x
   x = 1,834,122.23/1,381.47
6. Step 6: Final answer
   x = 1,327.66