Finding the Fourth Proportional to 1,538.82, 2,123.58 and 840.24

Step by Step Solution

1. Step 1: Write the proportion equation
   1,538.82 : 2,123.58 = 840.24 : x
2. Step 2: Convert to fraction form
   1,538.82/2,123.58 = 840.24/x
3. Step 3: Cross multiply
   1,538.82x = 2,123.58 × 840.24
4. Step 4: Simplify right side
   1,538.82x = 1,784,316.86
5. Step 5: Solve for x
   x = 1,784,316.86/1,538.82
6. Step 6: Final answer
   x = 1,159.54