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Finding the Fourth Proportional to 427, 640.38 and 210.34

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Solution

The fourth proportional to 427, 640.38 and 210.34 is: 315.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    427 : 640.38 = 210.34 : x
  2. Step 2: Convert to fraction form
    427/640.38 = 210.34/x
  3. Step 3: Cross multiply
    427x = 640.38 × 210.34
  4. Step 4: Simplify right side
    427x = 134,697.53
  5. Step 5: Solve for x
    x = 134,697.53/427
  6. Step 6: Final answer
    x = 315.45

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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.