Finding the Fourth Proportional to 42,881.67, 64,335.74 and 19,209.15

Step by Step Solution

1. Step 1: Write the proportion equation
   42,881.67 : 64,335.74 = 19,209.15 : x
2. Step 2: Convert to fraction form
   42,881.67/64,335.74 = 19,209.15/x
3. Step 3: Cross multiply
   42,881.67x = 64,335.74 × 19,209.15
4. Step 4: Simplify right side
   42,881.67x = 1,235,834,783.98
5. Step 5: Solve for x
   x = 1,235,834,783.98/42,881.67
6. Step 6: Final answer
   x = 28,819.65