Finding the Fourth Proportional to 780.42, 1,073.61 and 674.72

Step by Step Solution

1. Step 1: Write the proportion equation
   780.42 : 1,073.61 = 674.72 : x
2. Step 2: Convert to fraction form
   780.42/1,073.61 = 674.72/x
3. Step 3: Cross multiply
   780.42x = 1,073.61 × 674.72
4. Step 4: Simplify right side
   780.42x = 724,386.14
5. Step 5: Solve for x
   x = 724,386.14/780.42
6. Step 6: Final answer
   x = 928.20