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Finding the Fourth Proportional to 289.65, 399.56 and 210.88

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Solution

The fourth proportional to 289.65, 399.56 and 210.88 is: 290.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.65 : 399.56 = 210.88 : x
  2. Step 2: Convert to fraction form
    289.65/399.56 = 210.88/x
  3. Step 3: Cross multiply
    289.65x = 399.56 × 210.88
  4. Step 4: Simplify right side
    289.65x = 84,257.16
  5. Step 5: Solve for x
    x = 84,257.16/289.65
  6. Step 6: Final answer
    x = 290.89

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.