Finding the Fourth Proportional to 1,019.30, 1,406.82 and 646.70

Step by Step Solution

1. Step 1: Write the proportion equation
   1,019.30 : 1,406.82 = 646.70 : x
2. Step 2: Convert to fraction form
   1,019.30/1,406.82 = 646.70/x
3. Step 3: Cross multiply
   1,019.30x = 1,406.82 × 646.70
4. Step 4: Simplify right side
   1,019.30x = 909,790.49
5. Step 5: Solve for x
   x = 909,790.49/1,019.30
6. Step 6: Final answer
   x = 892.56