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Finding the Fourth Proportional to 281.00, 421.55 and 85.99

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Solution

The fourth proportional to 281.00, 421.55 and 85.99 is: 129.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    281.00 : 421.55 = 85.99 : x
  2. Step 2: Convert to fraction form
    281.00/421.55 = 85.99/x
  3. Step 3: Cross multiply
    281.00x = 421.55 × 85.99
  4. Step 4: Simplify right side
    281.00x = 36,249.08
  5. Step 5: Solve for x
    x = 36,249.08/281.00
  6. Step 6: Final answer
    x = 129.00

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.