Finding the Fourth Proportional to 1,917.60, 2,875.62 and 684.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,917.60 : 2,875.62 = 684.72 : x
2. Step 2: Convert to fraction form
   1,917.60/2,875.62 = 684.72/x
3. Step 3: Cross multiply
   1,917.60x = 2,875.62 × 684.72
4. Step 4: Simplify right side
   1,917.60x = 1,968,994.53
5. Step 5: Solve for x
   x = 1,968,994.53/1,917.60
6. Step 6: Final answer
   x = 1,026.80