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Finding the Fourth Proportional to 328.45, 491.72 and 256.09

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Solution

The fourth proportional to 328.45, 491.72 and 256.09 is: 383.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    328.45 : 491.72 = 256.09 : x
  2. Step 2: Convert to fraction form
    328.45/491.72 = 256.09/x
  3. Step 3: Cross multiply
    328.45x = 491.72 × 256.09
  4. Step 4: Simplify right side
    328.45x = 125,924.57
  5. Step 5: Solve for x
    x = 125,924.57/328.45
  6. Step 6: Final answer
    x = 383.39

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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.