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Finding the Fourth Proportional to 528.11, 728.43 and 318.12

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Solution

The fourth proportional to 528.11, 728.43 and 318.12 is: 438.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.11 : 728.43 = 318.12 : x
  2. Step 2: Convert to fraction form
    528.11/728.43 = 318.12/x
  3. Step 3: Cross multiply
    528.11x = 728.43 × 318.12
  4. Step 4: Simplify right side
    528.11x = 231,728.15
  5. Step 5: Solve for x
    x = 231,728.15/528.11
  6. Step 6: Final answer
    x = 438.79

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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.