Finding the Fourth Proportional to 1,378.09, 1,901.78 and 788.59

Step by Step Solution

1. Step 1: Write the proportion equation
   1,378.09 : 1,901.78 = 788.59 : x
2. Step 2: Convert to fraction form
   1,378.09/1,901.78 = 788.59/x
3. Step 3: Cross multiply
   1,378.09x = 1,901.78 × 788.59
4. Step 4: Simplify right side
   1,378.09x = 1,499,724.69
5. Step 5: Solve for x
   x = 1,499,724.69/1,378.09
6. Step 6: Final answer
   x = 1,088.26