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Finding the Fourth Proportional to 421.82, 581.91 and 328.40

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Solution

The fourth proportional to 421.82, 581.91 and 328.40 is: 453.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.82 : 581.91 = 328.40 : x
  2. Step 2: Convert to fraction form
    421.82/581.91 = 328.40/x
  3. Step 3: Cross multiply
    421.82x = 581.91 × 328.40
  4. Step 4: Simplify right side
    421.82x = 191,099.24
  5. Step 5: Solve for x
    x = 191,099.24/421.82
  6. Step 6: Final answer
    x = 453.04

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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.