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Finding the Fourth Proportional to 397.40, 548.30 and 287.16

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Solution

The fourth proportional to 397.40, 548.30 and 287.16 is: 396.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    397.40 : 548.30 = 287.16 : x
  2. Step 2: Convert to fraction form
    397.40/548.30 = 287.16/x
  3. Step 3: Cross multiply
    397.40x = 548.30 × 287.16
  4. Step 4: Simplify right side
    397.40x = 157,449.83
  5. Step 5: Solve for x
    x = 157,449.83/397.40
  6. Step 6: Final answer
    x = 396.20

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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.