Finding the Fourth Proportional to 28,591.30, 42,934.47 and 19,291.15

Step by Step Solution

1. Step 1: Write the proportion equation
   28,591.30 : 42,934.47 = 19,291.15 : x
2. Step 2: Convert to fraction form
   28,591.30/42,934.47 = 19,291.15/x
3. Step 3: Cross multiply
   28,591.30x = 42,934.47 × 19,291.15
4. Step 4: Simplify right side
   28,591.30x = 828,255,300.94
5. Step 5: Solve for x
   x = 828,255,300.94/28,591.30
6. Step 6: Final answer
   x = 28,968.79