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Finding the Fourth Proportional to 638.63, 881.29 and 355.06

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Solution

The fourth proportional to 638.63, 881.29 and 355.06 is: 489.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.63 : 881.29 = 355.06 : x
  2. Step 2: Convert to fraction form
    638.63/881.29 = 355.06/x
  3. Step 3: Cross multiply
    638.63x = 881.29 × 355.06
  4. Step 4: Simplify right side
    638.63x = 312,914.76
  5. Step 5: Solve for x
    x = 312,914.76/638.63
  6. Step 6: Final answer
    x = 489.98

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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.