Finding the Fourth Proportional to 1,117.98, 1,677.35 and 784.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,117.98 : 1,677.35 = 784.78 : x
2. Step 2: Convert to fraction form
   1,117.98/1,677.35 = 784.78/x
3. Step 3: Cross multiply
   1,117.98x = 1,677.35 × 784.78
4. Step 4: Simplify right side
   1,117.98x = 1,316,348.50
5. Step 5: Solve for x
   x = 1,316,348.50/1,117.98
6. Step 6: Final answer
   x = 1,177.43