Finding the Fourth Proportional to 81,459.60, 112,507.56 and 64,896.72

Step by Step Solution

1. Step 1: Write the proportion equation
   81,459.60 : 112,507.56 = 64,896.72 : x
2. Step 2: Convert to fraction form
   81,459.60/112,507.56 = 64,896.72/x
3. Step 3: Cross multiply
   81,459.60x = 112,507.56 × 64,896.72
4. Step 4: Simplify right side
   81,459.60x = 7,301,371,619.20
5. Step 5: Solve for x
   x = 7,301,371,619.20/81,459.60
6. Step 6: Final answer
   x = 89,631.81