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Finding the Fourth Proportional to 485.91, 728.87 and 290.97

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Solution

The fourth proportional to 485.91, 728.87 and 290.97 is: 436.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.91 : 728.87 = 290.97 : x
  2. Step 2: Convert to fraction form
    485.91/728.87 = 290.97/x
  3. Step 3: Cross multiply
    485.91x = 728.87 × 290.97
  4. Step 4: Simplify right side
    485.91x = 212,078.94
  5. Step 5: Solve for x
    x = 212,078.94/485.91
  6. Step 6: Final answer
    x = 436.45

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.