Finding the Fourth Proportional to 1,875.36, 2,811.52 and 780.54

Step by Step Solution

1. Step 1: Write the proportion equation
   1,875.36 : 2,811.52 = 780.54 : x
2. Step 2: Convert to fraction form
   1,875.36/2,811.52 = 780.54/x
3. Step 3: Cross multiply
   1,875.36x = 2,811.52 × 780.54
4. Step 4: Simplify right side
   1,875.36x = 2,194,503.82
5. Step 5: Solve for x
   x = 2,194,503.82/1,875.36
6. Step 6: Final answer
   x = 1,170.18