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Finding the Fourth Proportional to 398.06, 549.36 and 287.90

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Solution

The fourth proportional to 398.06, 549.36 and 287.90 is: 397.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    398.06 : 549.36 = 287.90 : x
  2. Step 2: Convert to fraction form
    398.06/549.36 = 287.90/x
  3. Step 3: Cross multiply
    398.06x = 549.36 × 287.90
  4. Step 4: Simplify right side
    398.06x = 158,160.74
  5. Step 5: Solve for x
    x = 158,160.74/398.06
  6. Step 6: Final answer
    x = 397.33

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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.