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Finding the Fourth Proportional to 328.78, 454.12 and 289.47

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Solution

The fourth proportional to 328.78, 454.12 and 289.47 is: 399.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    328.78 : 454.12 = 289.47 : x
  2. Step 2: Convert to fraction form
    328.78/454.12 = 289.47/x
  3. Step 3: Cross multiply
    328.78x = 454.12 × 289.47
  4. Step 4: Simplify right side
    328.78x = 131,452.67
  5. Step 5: Solve for x
    x = 131,452.67/328.78
  6. Step 6: Final answer
    x = 399.82

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.