Finding the Fourth Proportional to 1,312.17, 1,810.89 and 722.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,312.17 : 1,810.89 = 722.72 : x
2. Step 2: Convert to fraction form
   1,312.17/1,810.89 = 722.72/x
3. Step 3: Cross multiply
   1,312.17x = 1,810.89 × 722.72
4. Step 4: Simplify right side
   1,312.17x = 1,308,757.37
5. Step 5: Solve for x
   x = 1,308,757.37/1,312.17
6. Step 6: Final answer
   x = 997.40