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Finding the Fourth Proportional to 290.39, 399.39 and 253.58

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Solution

The fourth proportional to 290.39, 399.39 and 253.58 is: 348.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.39 : 399.39 = 253.58 : x
  2. Step 2: Convert to fraction form
    290.39/399.39 = 253.58/x
  3. Step 3: Cross multiply
    290.39x = 399.39 × 253.58
  4. Step 4: Simplify right side
    290.39x = 101,277.32
  5. Step 5: Solve for x
    x = 101,277.32/290.39
  6. Step 6: Final answer
    x = 348.76

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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.