Finding the Fourth Proportional to 2,097.60, 3,146.91 and 636.78

Step by Step Solution

1. Step 1: Write the proportion equation
   2,097.60 : 3,146.91 = 636.78 : x
2. Step 2: Convert to fraction form
   2,097.60/3,146.91 = 636.78/x
3. Step 3: Cross multiply
   2,097.60x = 3,146.91 × 636.78
4. Step 4: Simplify right side
   2,097.60x = 2,003,889.35
5. Step 5: Solve for x
   x = 2,003,889.35/2,097.60
6. Step 6: Final answer
   x = 955.32