Finding the Fourth Proportional to 1,128.32, 1,556.92 and 630.86

Step by Step Solution

1. Step 1: Write the proportion equation
   1,128.32 : 1,556.92 = 630.86 : x
2. Step 2: Convert to fraction form
   1,128.32/1,556.92 = 630.86/x
3. Step 3: Cross multiply
   1,128.32x = 1,556.92 × 630.86
4. Step 4: Simplify right side
   1,128.32x = 982,198.55
5. Step 5: Solve for x
   x = 982,198.55/1,128.32
6. Step 6: Final answer
   x = 870.50