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Finding the Fourth Proportional to 638.84, 957.64 and 205.70

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Solution

The fourth proportional to 638.84, 957.64 and 205.70 is: 308.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.84 : 957.64 = 205.70 : x
  2. Step 2: Convert to fraction form
    638.84/957.64 = 205.70/x
  3. Step 3: Cross multiply
    638.84x = 957.64 × 205.70
  4. Step 4: Simplify right side
    638.84x = 196,986.55
  5. Step 5: Solve for x
    x = 196,986.55/638.84
  6. Step 6: Final answer
    x = 308.35

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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.