Finding the Fourth Proportional to 1,107.72, 1,656.50 and 830.25

Step by Step Solution

1. Step 1: Write the proportion equation
   1,107.72 : 1,656.50 = 830.25 : x
2. Step 2: Convert to fraction form
   1,107.72/1,656.50 = 830.25/x
3. Step 3: Cross multiply
   1,107.72x = 1,656.50 × 830.25
4. Step 4: Simplify right side
   1,107.72x = 1,375,304.97
5. Step 5: Solve for x
   x = 1,375,304.97/1,107.72
6. Step 6: Final answer
   x = 1,241.56