Finding the Fourth Proportional to 1,773.72, 2,447.75 and 987.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,773.72 : 2,447.75 = 987.78 : x
2. Step 2: Convert to fraction form
   1,773.72/2,447.75 = 987.78/x
3. Step 3: Cross multiply
   1,773.72x = 2,447.75 × 987.78
4. Step 4: Simplify right side
   1,773.72x = 2,417,838.50
5. Step 5: Solve for x
   x = 2,417,838.50/1,773.72
6. Step 6: Final answer
   x = 1,363.15