Finding the Fourth Proportional to 1,131.48, 1,698.72 and 645.48

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.48 : 1,698.72 = 645.48 : x
2. Step 2: Convert to fraction form
   1,131.48/1,698.72 = 645.48/x
3. Step 3: Cross multiply
   1,131.48x = 1,698.72 × 645.48
4. Step 4: Simplify right side
   1,131.48x = 1,096,489.79
5. Step 5: Solve for x
   x = 1,096,489.79/1,131.48
6. Step 6: Final answer
   x = 969.08