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Finding the Fourth Proportional to 290.66, 400.82 and 207.78

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Solution

The fourth proportional to 290.66, 400.82 and 207.78 is: 286.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.66 : 400.82 = 207.78 : x
  2. Step 2: Convert to fraction form
    290.66/400.82 = 207.78/x
  3. Step 3: Cross multiply
    290.66x = 400.82 × 207.78
  4. Step 4: Simplify right side
    290.66x = 83,282.38
  5. Step 5: Solve for x
    x = 83,282.38/290.66
  6. Step 6: Final answer
    x = 286.53

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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.