Finding the Fourth Proportional to 1,012.32, 1,397.07 and 619.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,012.32 : 1,397.07 = 619.56 : x
2. Step 2: Convert to fraction form
   1,012.32/1,397.07 = 619.56/x
3. Step 3: Cross multiply
   1,012.32x = 1,397.07 × 619.56
4. Step 4: Simplify right side
   1,012.32x = 865,568.69
5. Step 5: Solve for x
   x = 865,568.69/1,012.32
6. Step 6: Final answer
   x = 855.03