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Finding the Fourth Proportional to 290.56, 398.81 and 258.76

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Solution

The fourth proportional to 290.56, 398.81 and 258.76 is: 355.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.56 : 398.81 = 258.76 : x
  2. Step 2: Convert to fraction form
    290.56/398.81 = 258.76/x
  3. Step 3: Cross multiply
    290.56x = 398.81 × 258.76
  4. Step 4: Simplify right side
    290.56x = 103,194.78
  5. Step 5: Solve for x
    x = 103,194.78/290.56
  6. Step 6: Final answer
    x = 355.16

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.