Finding the Fourth Proportional to 2,021.40, 3,031.48 and 788.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,021.40 : 3,031.48 = 788.72 : x
2. Step 2: Convert to fraction form
   2,021.40/3,031.48 = 788.72/x
3. Step 3: Cross multiply
   2,021.40x = 3,031.48 × 788.72
4. Step 4: Simplify right side
   2,021.40x = 2,390,988.91
5. Step 5: Solve for x
   x = 2,390,988.91/2,021.40
6. Step 6: Final answer
   x = 1,182.84