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Finding the Fourth Proportional to 328.38, 491.55 and 291.79

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Solution

The fourth proportional to 328.38, 491.55 and 291.79 is: 436.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    328.38 : 491.55 = 291.79 : x
  2. Step 2: Convert to fraction form
    328.38/491.55 = 291.79/x
  3. Step 3: Cross multiply
    328.38x = 491.55 × 291.79
  4. Step 4: Simplify right side
    328.38x = 143,429.37
  5. Step 5: Solve for x
    x = 143,429.37/328.38
  6. Step 6: Final answer
    x = 436.78

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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.