Finding the Fourth Proportional to 1,034.71, 1,428.15 and 641.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,034.71 : 1,428.15 = 641.50 : x
2. Step 2: Convert to fraction form
   1,034.71/1,428.15 = 641.50/x
3. Step 3: Cross multiply
   1,034.71x = 1,428.15 × 641.50
4. Step 4: Simplify right side
   1,034.71x = 916,158.23
5. Step 5: Solve for x
   x = 916,158.23/1,034.71
6. Step 6: Final answer
   x = 885.43