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Finding the Fourth Proportional to 521.65, 720.05 and 353.64

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Solution

The fourth proportional to 521.65, 720.05 and 353.64 is: 488.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.65 : 720.05 = 353.64 : x
  2. Step 2: Convert to fraction form
    521.65/720.05 = 353.64/x
  3. Step 3: Cross multiply
    521.65x = 720.05 × 353.64
  4. Step 4: Simplify right side
    521.65x = 254,638.48
  5. Step 5: Solve for x
    x = 254,638.48/521.65
  6. Step 6: Final answer
    x = 488.14

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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.