Finding the Fourth Proportional to 1,090.31, 1,503.88 and 697.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,090.31 : 1,503.88 = 697.15 : x
2. Step 2: Convert to fraction form
   1,090.31/1,503.88 = 697.15/x
3. Step 3: Cross multiply
   1,090.31x = 1,503.88 × 697.15
4. Step 4: Simplify right side
   1,090.31x = 1,048,429.94
5. Step 5: Solve for x
   x = 1,048,429.94/1,090.31
6. Step 6: Final answer
   x = 961.59