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Finding the Fourth Proportional to 298.65, 410.90 and 290.55

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Solution

The fourth proportional to 298.65, 410.90 and 290.55 is: 399.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    298.65 : 410.90 = 290.55 : x
  2. Step 2: Convert to fraction form
    298.65/410.90 = 290.55/x
  3. Step 3: Cross multiply
    298.65x = 410.90 × 290.55
  4. Step 4: Simplify right side
    298.65x = 119,385.54
  5. Step 5: Solve for x
    x = 119,385.54/298.65
  6. Step 6: Final answer
    x = 399.75

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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.