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Finding the Fourth Proportional to 638.19, 955.63 and 442.90

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Solution

The fourth proportional to 638.19, 955.63 and 442.90 is: 663.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.19 : 955.63 = 442.90 : x
  2. Step 2: Convert to fraction form
    638.19/955.63 = 442.90/x
  3. Step 3: Cross multiply
    638.19x = 955.63 × 442.90
  4. Step 4: Simplify right side
    638.19x = 423,248.53
  5. Step 5: Solve for x
    x = 423,248.53/638.19
  6. Step 6: Final answer
    x = 663.20

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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.