Finding the Fourth Proportional to 42,080.63, 63,110.10 and 12,491.78

Step by Step Solution

1. Step 1: Write the proportion equation
   42,080.63 : 63,110.10 = 12,491.78 : x
2. Step 2: Convert to fraction form
   42,080.63/63,110.10 = 12,491.78/x
3. Step 3: Cross multiply
   42,080.63x = 63,110.10 × 12,491.78
4. Step 4: Simplify right side
   42,080.63x = 788,357,484.98
5. Step 5: Solve for x
   x = 788,357,484.98/42,080.63
6. Step 6: Final answer
   x = 18,734.45