Finding the Fourth Proportional to 28,281, 42,402.78 and 13,492.20

Step by Step Solution

1. Step 1: Write the proportion equation
   28,281 : 42,402.78 = 13,492.20 : x
2. Step 2: Convert to fraction form
   28,281/42,402.78 = 13,492.20/x
3. Step 3: Cross multiply
   28,281x = 42,402.78 × 13,492.20
4. Step 4: Simplify right side
   28,281x = 572,106,788.32
5. Step 5: Solve for x
   x = 572,106,788.32/28,281
6. Step 6: Final answer
   x = 20,229.37