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Finding the Fourth Proportional to 290.80, 400.88 and 207.76

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Solution

The fourth proportional to 290.80, 400.88 and 207.76 is: 286.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.80 : 400.88 = 207.76 : x
  2. Step 2: Convert to fraction form
    290.80/400.88 = 207.76/x
  3. Step 3: Cross multiply
    290.80x = 400.88 × 207.76
  4. Step 4: Simplify right side
    290.80x = 83,286.83
  5. Step 5: Solve for x
    x = 83,286.83/290.80
  6. Step 6: Final answer
    x = 286.41

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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.