Finding the Fourth Proportional to 42,071.42, 63,113.40 and 12,485.76

Step by Step Solution

1. Step 1: Write the proportion equation
   42,071.42 : 63,113.40 = 12,485.76 : x
2. Step 2: Convert to fraction form
   42,071.42/63,113.40 = 12,485.76/x
3. Step 3: Cross multiply
   42,071.42x = 63,113.40 × 12,485.76
4. Step 4: Simplify right side
   42,071.42x = 788,018,765.18
5. Step 5: Solve for x
   x = 788,018,765.18/42,071.42
6. Step 6: Final answer
   x = 18,730.50