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Finding the Fourth Proportional to 638.13, 957.21 and 442.07

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Solution

The fourth proportional to 638.13, 957.21 and 442.07 is: 663.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.13 : 957.21 = 442.07 : x
  2. Step 2: Convert to fraction form
    638.13/957.21 = 442.07/x
  3. Step 3: Cross multiply
    638.13x = 957.21 × 442.07
  4. Step 4: Simplify right side
    638.13x = 423,153.82
  5. Step 5: Solve for x
    x = 423,153.82/638.13
  6. Step 6: Final answer
    x = 663.12

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.