Finding the Fourth Proportional to 1,015.31, 1,522.02 and 429.41

Step by Step Solution

1. Step 1: Write the proportion equation
   1,015.31 : 1,522.02 = 429.41 : x
2. Step 2: Convert to fraction form
   1,015.31/1,522.02 = 429.41/x
3. Step 3: Cross multiply
   1,015.31x = 1,522.02 × 429.41
4. Step 4: Simplify right side
   1,015.31x = 653,570.61
5. Step 5: Solve for x
   x = 653,570.61/1,015.31
6. Step 6: Final answer
   x = 643.72