Finding the Fourth Proportional to 1,975.86, 2,961.65 and 878.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,975.86 : 2,961.65 = 878.72 : x
2. Step 2: Convert to fraction form
   1,975.86/2,961.65 = 878.72/x
3. Step 3: Cross multiply
   1,975.86x = 2,961.65 × 878.72
4. Step 4: Simplify right side
   1,975.86x = 2,602,441.89
5. Step 5: Solve for x
   x = 2,602,441.89/1,975.86
6. Step 6: Final answer
   x = 1,317.12