Finding the Fourth Proportional to 1,131.90, 1,561.68 and 712.67

Step by Step Solution

1. Step 1: Write the proportion equation
   1,131.90 : 1,561.68 = 712.67 : x
2. Step 2: Convert to fraction form
   1,131.90/1,561.68 = 712.67/x
3. Step 3: Cross multiply
   1,131.90x = 1,561.68 × 712.67
4. Step 4: Simplify right side
   1,131.90x = 1,112,967.39
5. Step 5: Solve for x
   x = 1,112,967.39/1,131.90
6. Step 6: Final answer
   x = 983.27