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Finding the Fourth Proportional to 398.90, 549.50 and 288.06

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Solution

The fourth proportional to 398.90, 549.50 and 288.06 is: 396.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.90 : 549.50 = 288.06 : x
  2. Step 2: Convert to fraction form
    398.90/549.50 = 288.06/x
  3. Step 3: Cross multiply
    398.90x = 549.50 × 288.06
  4. Step 4: Simplify right side
    398.90x = 158,288.97
  5. Step 5: Solve for x
    x = 158,288.97/398.90
  6. Step 6: Final answer
    x = 396.81

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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.