Finding the Fourth Proportional to 1,538.38, 2,122.96 and 839.76

Step by Step Solution

1. Step 1: Write the proportion equation
   1,538.38 : 2,122.96 = 839.76 : x
2. Step 2: Convert to fraction form
   1,538.38/2,122.96 = 839.76/x
3. Step 3: Cross multiply
   1,538.38x = 2,122.96 × 839.76
4. Step 4: Simplify right side
   1,538.38x = 1,782,776.89
5. Step 5: Solve for x
   x = 1,782,776.89/1,538.38
6. Step 6: Final answer
   x = 1,158.87