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Finding the Fourth Proportional to 638.58, 957.49 and 309.40

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Solution

The fourth proportional to 638.58, 957.49 and 309.40 is: 463.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.58 : 957.49 = 309.40 : x
  2. Step 2: Convert to fraction form
    638.58/957.49 = 309.40/x
  3. Step 3: Cross multiply
    638.58x = 957.49 × 309.40
  4. Step 4: Simplify right side
    638.58x = 296,247.41
  5. Step 5: Solve for x
    x = 296,247.41/638.58
  6. Step 6: Final answer
    x = 463.92

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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.