Finding the Fourth Proportional to 42,990.19, 64,491.74 and 13,410.34

Step by Step Solution

1. Step 1: Write the proportion equation
   42,990.19 : 64,491.74 = 13,410.34 : x
2. Step 2: Convert to fraction form
   42,990.19/64,491.74 = 13,410.34/x
3. Step 3: Cross multiply
   42,990.19x = 64,491.74 × 13,410.34
4. Step 4: Simplify right side
   42,990.19x = 864,856,160.59
5. Step 5: Solve for x
   x = 864,856,160.59/42,990.19
6. Step 6: Final answer
   x = 20,117.52