Finding the Fourth Proportional to 90,915.60, 136,394.82 and 28,586.10

Step by Step Solution

1. Step 1: Write the proportion equation
   90,915.60 : 136,394.82 = 28,586.10 : x
2. Step 2: Convert to fraction form
   90,915.60/136,394.82 = 28,586.10/x
3. Step 3: Cross multiply
   90,915.60x = 136,394.82 × 28,586.10
4. Step 4: Simplify right side
   90,915.60x = 3,898,995,964.00
5. Step 5: Solve for x
   x = 3,898,995,964.00/90,915.60
6. Step 6: Final answer
   x = 42,885.88