Finding the Fourth Proportional to 1,538.59, 2,123.28 and 839.97

Step by Step Solution

1. Step 1: Write the proportion equation
   1,538.59 : 2,123.28 = 839.97 : x
2. Step 2: Convert to fraction form
   1,538.59/2,123.28 = 839.97/x
3. Step 3: Cross multiply
   1,538.59x = 2,123.28 × 839.97
4. Step 4: Simplify right side
   1,538.59x = 1,783,491.50
5. Step 5: Solve for x
   x = 1,783,491.50/1,538.59
6. Step 6: Final answer
   x = 1,159.17