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Finding the Fourth Proportional to 521.21, 720.05 and 442.40

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Solution

The fourth proportional to 521.21, 720.05 and 442.40 is: 611.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    521.21 : 720.05 = 442.40 : x
  2. Step 2: Convert to fraction form
    521.21/720.05 = 442.40/x
  3. Step 3: Cross multiply
    521.21x = 720.05 × 442.40
  4. Step 4: Simplify right side
    521.21x = 318,544.31
  5. Step 5: Solve for x
    x = 318,544.31/521.21
  6. Step 6: Final answer
    x = 611.16

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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.