Finding the Fourth Proportional to 1,687.88, 2,533.12 and 1,171.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,687.88 : 2,533.12 = 1,171.50 : x
2. Step 2: Convert to fraction form
   1,687.88/2,533.12 = 1,171.50/x
3. Step 3: Cross multiply
   1,687.88x = 2,533.12 × 1,171.50
4. Step 4: Simplify right side
   1,687.88x = 2,967,547.15
5. Step 5: Solve for x
   x = 2,967,547.15/1,687.88
6. Step 6: Final answer
   x = 1,758.16