Finding the Fourth Proportional to 1,143.31, 1,577.78 and 619.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,143.31 : 1,577.78 = 619.34 : x
2. Step 2: Convert to fraction form
   1,143.31/1,577.78 = 619.34/x
3. Step 3: Cross multiply
   1,143.31x = 1,577.78 × 619.34
4. Step 4: Simplify right side
   1,143.31x = 977,182.27
5. Step 5: Solve for x
   x = 977,182.27/1,143.31
6. Step 6: Final answer
   x = 854.70