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Finding the Fourth Proportional to 289.42, 434.28 and 221.38

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Solution

The fourth proportional to 289.42, 434.28 and 221.38 is: 332.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.42 : 434.28 = 221.38 : x
  2. Step 2: Convert to fraction form
    289.42/434.28 = 221.38/x
  3. Step 3: Cross multiply
    289.42x = 434.28 × 221.38
  4. Step 4: Simplify right side
    289.42x = 96,137.63
  5. Step 5: Solve for x
    x = 96,137.63/289.42
  6. Step 6: Final answer
    x = 332.18

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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.