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Finding the Fourth Proportional to 638.21, 957.41 and 313.60

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Solution

The fourth proportional to 638.21, 957.41 and 313.60 is: 470.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.21 : 957.41 = 313.60 : x
  2. Step 2: Convert to fraction form
    638.21/957.41 = 313.60/x
  3. Step 3: Cross multiply
    638.21x = 957.41 × 313.60
  4. Step 4: Simplify right side
    638.21x = 300,243.78
  5. Step 5: Solve for x
    x = 300,243.78/638.21
  6. Step 6: Final answer
    x = 470.45

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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.