Finding the Fourth Proportional to 90,499.30, 124,774.23 and 64,688.74

Step by Step Solution

1. Step 1: Write the proportion equation
   90,499.30 : 124,774.23 = 64,688.74 : x
2. Step 2: Convert to fraction form
   90,499.30/124,774.23 = 64,688.74/x
3. Step 3: Cross multiply
   90,499.30x = 124,774.23 × 64,688.74
4. Step 4: Simplify right side
   90,499.30x = 8,071,487,723.17
5. Step 5: Solve for x
   x = 8,071,487,723.17/90,499.30
6. Step 6: Final answer
   x = 89,188.40