Finding the Fourth Proportional to 1,315.47, 1,964.73 and 1,191.81

Step by Step Solution

1. Step 1: Write the proportion equation
   1,315.47 : 1,964.73 = 1,191.81 : x
2. Step 2: Convert to fraction form
   1,315.47/1,964.73 = 1,191.81/x
3. Step 3: Cross multiply
   1,315.47x = 1,964.73 × 1,191.81
4. Step 4: Simplify right side
   1,315.47x = 2,341,584.86
5. Step 5: Solve for x
   x = 2,341,584.86/1,315.47
6. Step 6: Final answer
   x = 1,780.04