Finding the Fourth Proportional to 1,012.95, 1,522.41 and 840.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,012.95 : 1,522.41 = 840.72 : x
2. Step 2: Convert to fraction form
   1,012.95/1,522.41 = 840.72/x
3. Step 3: Cross multiply
   1,012.95x = 1,522.41 × 840.72
4. Step 4: Simplify right side
   1,012.95x = 1,279,920.54
5. Step 5: Solve for x
   x = 1,279,920.54/1,012.95
6. Step 6: Final answer
   x = 1,263.56