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Finding the Fourth Proportional to 528.30, 728.21 and 423.21

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Solution

The fourth proportional to 528.30, 728.21 and 423.21 is: 583.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.30 : 728.21 = 423.21 : x
  2. Step 2: Convert to fraction form
    528.30/728.21 = 423.21/x
  3. Step 3: Cross multiply
    528.30x = 728.21 × 423.21
  4. Step 4: Simplify right side
    528.30x = 308,183.64
  5. Step 5: Solve for x
    x = 308,183.64/528.30
  6. Step 6: Final answer
    x = 583.35

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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.