Finding the Fourth Proportional to 28,612.28, 42,911.86 and 7,837.40

Step by Step Solution

1. Step 1: Write the proportion equation
   28,612.28 : 42,911.86 = 7,837.40 : x
2. Step 2: Convert to fraction form
   28,612.28/42,911.86 = 7,837.40/x
3. Step 3: Cross multiply
   28,612.28x = 42,911.86 × 7,837.40
4. Step 4: Simplify right side
   28,612.28x = 336,317,411.56
5. Step 5: Solve for x
   x = 336,317,411.56/28,612.28
6. Step 6: Final answer
   x = 11,754.30