Finding the Fourth Proportional to 1,705.55, 2,554.71 and 781.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,705.55 : 2,554.71 = 781.88 : x
2. Step 2: Convert to fraction form
   1,705.55/2,554.71 = 781.88/x
3. Step 3: Cross multiply
   1,705.55x = 2,554.71 × 781.88
4. Step 4: Simplify right side
   1,705.55x = 1,997,463.88
5. Step 5: Solve for x
   x = 1,997,463.88/1,705.55
6. Step 6: Final answer
   x = 1,171.16