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Finding the Fourth Proportional to 528.26, 728.60 and 318.20

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Solution

The fourth proportional to 528.26, 728.60 and 318.20 is: 438.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.26 : 728.60 = 318.20 : x
  2. Step 2: Convert to fraction form
    528.26/728.60 = 318.20/x
  3. Step 3: Cross multiply
    528.26x = 728.60 × 318.20
  4. Step 4: Simplify right side
    528.26x = 231,840.52
  5. Step 5: Solve for x
    x = 231,840.52/528.26
  6. Step 6: Final answer
    x = 438.88

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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.