Finding the Fourth Proportional to 1,312.18, 1,810.79 and 722.70

Step by Step Solution

1. Step 1: Write the proportion equation
   1,312.18 : 1,810.79 = 722.70 : x
2. Step 2: Convert to fraction form
   1,312.18/1,810.79 = 722.70/x
3. Step 3: Cross multiply
   1,312.18x = 1,810.79 × 722.70
4. Step 4: Simplify right side
   1,312.18x = 1,308,667.89
5. Step 5: Solve for x
   x = 1,308,667.89/1,312.18
6. Step 6: Final answer
   x = 997.32