Finding the Fourth Proportional to 1,091.51, 1,636.71 and 398.02

Step by Step Solution

1. Step 1: Write the proportion equation
   1,091.51 : 1,636.71 = 398.02 : x
2. Step 2: Convert to fraction form
   1,091.51/1,636.71 = 398.02/x
3. Step 3: Cross multiply
   1,091.51x = 1,636.71 × 398.02
4. Step 4: Simplify right side
   1,091.51x = 651,443.31
5. Step 5: Solve for x
   x = 651,443.31/1,091.51
6. Step 6: Final answer
   x = 596.83