Finding the Fourth Proportional to 13,909.68, 19,196.96 and 7,942.20

Step by Step Solution

1. Step 1: Write the proportion equation
   13,909.68 : 19,196.96 = 7,942.20 : x
2. Step 2: Convert to fraction form
   13,909.68/19,196.96 = 7,942.20/x
3. Step 3: Cross multiply
   13,909.68x = 19,196.96 × 7,942.20
4. Step 4: Simplify right side
   13,909.68x = 152,466,095.71
5. Step 5: Solve for x
   x = 152,466,095.71/13,909.68
6. Step 6: Final answer
   x = 10,961.15