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Finding the Fourth Proportional to 280.17, 420.39 and 126.18

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Solution

The fourth proportional to 280.17, 420.39 and 126.18 is: 189.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.17 : 420.39 = 126.18 : x
  2. Step 2: Convert to fraction form
    280.17/420.39 = 126.18/x
  3. Step 3: Cross multiply
    280.17x = 420.39 × 126.18
  4. Step 4: Simplify right side
    280.17x = 53,044.81
  5. Step 5: Solve for x
    x = 53,044.81/280.17
  6. Step 6: Final answer
    x = 189.33

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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.