Finding the Fourth Proportional to 1,378.32, 1,901.60 and 788.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,378.32 : 1,901.60 = 788.42 : x
2. Step 2: Convert to fraction form
   1,378.32/1,901.60 = 788.42/x
3. Step 3: Cross multiply
   1,378.32x = 1,901.60 × 788.42
4. Step 4: Simplify right side
   1,378.32x = 1,499,259.47
5. Step 5: Solve for x
   x = 1,499,259.47/1,378.32
6. Step 6: Final answer
   x = 1,087.74