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Finding the Fourth Proportional to 421.72, 582.72 and 328.70

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Solution

The fourth proportional to 421.72, 582.72 and 328.70 is: 454.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.72 : 582.72 = 328.70 : x
  2. Step 2: Convert to fraction form
    421.72/582.72 = 328.70/x
  3. Step 3: Cross multiply
    421.72x = 582.72 × 328.70
  4. Step 4: Simplify right side
    421.72x = 191,540.06
  5. Step 5: Solve for x
    x = 191,540.06/421.72
  6. Step 6: Final answer
    x = 454.19

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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.