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Finding the Fourth Proportional to 290.92, 400.30 and 280.82

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Solution

The fourth proportional to 290.92, 400.30 and 280.82 is: 386.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.92 : 400.30 = 280.82 : x
  2. Step 2: Convert to fraction form
    290.92/400.30 = 280.82/x
  3. Step 3: Cross multiply
    290.92x = 400.30 × 280.82
  4. Step 4: Simplify right side
    290.92x = 112,411.84
  5. Step 5: Solve for x
    x = 112,411.84/290.92
  6. Step 6: Final answer
    x = 386.40

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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.