Finding the Fourth Proportional to 1,131.16, 1,560.72 and 711.58

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.16 : 1,560.72 = 711.58 : x
2. Step 2: Convert to fraction form
   1,131.16/1,560.72 = 711.58/x
3. Step 3: Cross multiply
   1,131.16x = 1,560.72 × 711.58
4. Step 4: Simplify right side
   1,131.16x = 1,110,577.14
5. Step 5: Solve for x
   x = 1,110,577.14/1,131.16
6. Step 6: Final answer
   x = 981.80