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Finding the Fourth Proportional to 427.23, 640.54 and 210.76

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Solution

The fourth proportional to 427.23, 640.54 and 210.76 is: 315.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.23 : 640.54 = 210.76 : x
  2. Step 2: Convert to fraction form
    427.23/640.54 = 210.76/x
  3. Step 3: Cross multiply
    427.23x = 640.54 × 210.76
  4. Step 4: Simplify right side
    427.23x = 134,998.87
  5. Step 5: Solve for x
    x = 134,998.87/427.23
  6. Step 6: Final answer
    x = 315.99

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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.