Finding the Fourth Proportional to 1,312.25, 1,810.91 and 722.79

Step by Step Solution

1. Step 1: Write the proportion equation
   1,312.25 : 1,810.91 = 722.79 : x
2. Step 2: Convert to fraction form
   1,312.25/1,810.91 = 722.79/x
3. Step 3: Cross multiply
   1,312.25x = 1,810.91 × 722.79
4. Step 4: Simplify right side
   1,312.25x = 1,308,904.02
5. Step 5: Solve for x
   x = 1,308,904.02/1,312.25
6. Step 6: Final answer
   x = 997.45