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Finding the Fourth Proportional to 521.68, 720.16 and 397.36

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Solution

The fourth proportional to 521.68, 720.16 and 397.36 is: 548.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.68 : 720.16 = 397.36 : x
  2. Step 2: Convert to fraction form
    521.68/720.16 = 397.36/x
  3. Step 3: Cross multiply
    521.68x = 720.16 × 397.36
  4. Step 4: Simplify right side
    521.68x = 286,162.78
  5. Step 5: Solve for x
    x = 286,162.78/521.68
  6. Step 6: Final answer
    x = 548.54

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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.