Finding the Fourth Proportional to 21,914.96, 30,240.96 and 12,961.76

Step by Step Solution

1. Step 1: Write the proportion equation
   21,914.96 : 30,240.96 = 12,961.76 : x
2. Step 2: Convert to fraction form
   21,914.96/30,240.96 = 12,961.76/x
3. Step 3: Cross multiply
   21,914.96x = 30,240.96 × 12,961.76
4. Step 4: Simplify right side
   21,914.96x = 391,976,065.69
5. Step 5: Solve for x
   x = 391,976,065.69/21,914.96
6. Step 6: Final answer
   x = 17,886.23