Finding the Fourth Proportional to 1,429.47, 1,972.62 and 839.70

Step by Step Solution

1. Step 1: Write the proportion equation
   1,429.47 : 1,972.62 = 839.70 : x
2. Step 2: Convert to fraction form
   1,429.47/1,972.62 = 839.70/x
3. Step 3: Cross multiply
   1,429.47x = 1,972.62 × 839.70
4. Step 4: Simplify right side
   1,429.47x = 1,656,409.01
5. Step 5: Solve for x
   x = 1,656,409.01/1,429.47
6. Step 6: Final answer
   x = 1,158.76