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Finding the Fourth Proportional to 528.25, 728.69 and 318.30

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Solution

The fourth proportional to 528.25, 728.69 and 318.30 is: 439.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.25 : 728.69 = 318.30 : x
  2. Step 2: Convert to fraction form
    528.25/728.69 = 318.30/x
  3. Step 3: Cross multiply
    528.25x = 728.69 × 318.30
  4. Step 4: Simplify right side
    528.25x = 231,940.09
  5. Step 5: Solve for x
    x = 231,940.09/528.25
  6. Step 6: Final answer
    x = 439.07

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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.