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Finding the Fourth Proportional to 289.01, 399.10 and 210.78

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Solution

The fourth proportional to 289.01, 399.10 and 210.78 is: 291.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    289.01 : 399.10 = 210.78 : x
  2. Step 2: Convert to fraction form
    289.01/399.10 = 210.78/x
  3. Step 3: Cross multiply
    289.01x = 399.10 × 210.78
  4. Step 4: Simplify right side
    289.01x = 84,119.25
  5. Step 5: Solve for x
    x = 84,119.25/289.01
  6. Step 6: Final answer
    x = 291.07

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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.