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Finding the Fourth Proportional to 427.48, 640.78 and 324.54

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Solution

The fourth proportional to 427.48, 640.78 and 324.54 is: 486.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.48 : 640.78 = 324.54 : x
  2. Step 2: Convert to fraction form
    427.48/640.78 = 324.54/x
  3. Step 3: Cross multiply
    427.48x = 640.78 × 324.54
  4. Step 4: Simplify right side
    427.48x = 207,959.43
  5. Step 5: Solve for x
    x = 207,959.43/427.48
  6. Step 6: Final answer
    x = 486.48

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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.