Finding the Fourth Proportional to 1,105.34, 1,656.39 and 781.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,105.34 : 1,656.39 = 781.34 : x
2. Step 2: Convert to fraction form
   1,105.34/1,656.39 = 781.34/x
3. Step 3: Cross multiply
   1,105.34x = 1,656.39 × 781.34
4. Step 4: Simplify right side
   1,105.34x = 1,294,203.76
5. Step 5: Solve for x
   x = 1,294,203.76/1,105.34
6. Step 6: Final answer
   x = 1,170.86