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Finding the Fourth Proportional to 426.90, 640.17 and 290.01

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Solution

The fourth proportional to 426.90, 640.17 and 290.01 is: 434.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.90 : 640.17 = 290.01 : x
  2. Step 2: Convert to fraction form
    426.90/640.17 = 290.01/x
  3. Step 3: Cross multiply
    426.90x = 640.17 × 290.01
  4. Step 4: Simplify right side
    426.90x = 185,655.70
  5. Step 5: Solve for x
    x = 185,655.70/426.90
  6. Step 6: Final answer
    x = 434.89

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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.