Finding the Fourth Proportional to 1,142.67, 1,575.31 and 722.81

Step by Step Solution

1. Step 1: Write the proportion equation
   1,142.67 : 1,575.31 = 722.81 : x
2. Step 2: Convert to fraction form
   1,142.67/1,575.31 = 722.81/x
3. Step 3: Cross multiply
   1,142.67x = 1,575.31 × 722.81
4. Step 4: Simplify right side
   1,142.67x = 1,138,649.82
5. Step 5: Solve for x
   x = 1,138,649.82/1,142.67
6. Step 6: Final answer
   x = 996.48