Finding the Fourth Proportional to 282.59, 423.89 and 99.99

Step by Step Solution

1. Step 1: Write the proportion equation
   282.59 : 423.89 = 99.99 : x
2. Step 2: Convert to fraction form
   282.59/423.89 = 99.99/x
3. Step 3: Cross multiply
   282.59x = 423.89 × 99.99
4. Step 4: Simplify right side
   282.59x = 42,384.76
5. Step 5: Solve for x
   x = 42,384.76/282.59
6. Step 6: Final answer
   x = 149.99