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Finding the Fourth Proportional to 638.21, 956.63 and 312.89

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Solution

The fourth proportional to 638.21, 956.63 and 312.89 is: 469.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.21 : 956.63 = 312.89 : x
  2. Step 2: Convert to fraction form
    638.21/956.63 = 312.89/x
  3. Step 3: Cross multiply
    638.21x = 956.63 × 312.89
  4. Step 4: Simplify right side
    638.21x = 299,319.58
  5. Step 5: Solve for x
    x = 299,319.58/638.21
  6. Step 6: Final answer
    x = 469.00

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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.