Finding the Fourth Proportional to 1,317.91, 1,820.22 and 897.55

Step by Step Solution

1. Step 1: Write the proportion equation
   1,317.91 : 1,820.22 = 897.55 : x
2. Step 2: Convert to fraction form
   1,317.91/1,820.22 = 897.55/x
3. Step 3: Cross multiply
   1,317.91x = 1,820.22 × 897.55
4. Step 4: Simplify right side
   1,317.91x = 1,633,738.46
5. Step 5: Solve for x
   x = 1,633,738.46/1,317.91
6. Step 6: Final answer
   x = 1,239.64