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Finding the Fourth Proportional to 638.95, 957.04 and 309.39

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Solution

The fourth proportional to 638.95, 957.04 and 309.39 is: 463.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.95 : 957.04 = 309.39 : x
  2. Step 2: Convert to fraction form
    638.95/957.04 = 309.39/x
  3. Step 3: Cross multiply
    638.95x = 957.04 × 309.39
  4. Step 4: Simplify right side
    638.95x = 296,098.61
  5. Step 5: Solve for x
    x = 296,098.61/638.95
  6. Step 6: Final answer
    x = 463.41

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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.