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Finding the Fourth Proportional to 290.40, 400.71 and 159.39

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Solution

The fourth proportional to 290.40, 400.71 and 159.39 is: 219.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.40 : 400.71 = 159.39 : x
  2. Step 2: Convert to fraction form
    290.40/400.71 = 159.39/x
  3. Step 3: Cross multiply
    290.40x = 400.71 × 159.39
  4. Step 4: Simplify right side
    290.40x = 63,869.17
  5. Step 5: Solve for x
    x = 63,869.17/290.40
  6. Step 6: Final answer
    x = 219.94

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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.