Finding the Fourth Proportional to 21,856.76, 32,817.86 and 12,507.32

Step by Step Solution

1. Step 1: Write the proportion equation
   21,856.76 : 32,817.86 = 12,507.32 : x
2. Step 2: Convert to fraction form
   21,856.76/32,817.86 = 12,507.32/x
3. Step 3: Cross multiply
   21,856.76x = 32,817.86 × 12,507.32
4. Step 4: Simplify right side
   21,856.76x = 410,463,476.74
5. Step 5: Solve for x
   x = 410,463,476.74/21,856.76
6. Step 6: Final answer
   x = 18,779.70