Finding the Fourth Proportional to 1,034.96, 1,428.53 and 641.75

Step by Step Solution

1. Step 1: Write the proportion equation
   1,034.96 : 1,428.53 = 641.75 : x
2. Step 2: Convert to fraction form
   1,034.96/1,428.53 = 641.75/x
3. Step 3: Cross multiply
   1,034.96x = 1,428.53 × 641.75
4. Step 4: Simplify right side
   1,034.96x = 916,748.78
5. Step 5: Solve for x
   x = 916,748.78/1,034.96
6. Step 6: Final answer
   x = 885.79