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Finding the Fourth Proportional to 528.14, 728.87 and 388.89

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Solution

The fourth proportional to 528.14, 728.87 and 388.89 is: 536.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.14 : 728.87 = 388.89 : x
  2. Step 2: Convert to fraction form
    528.14/728.87 = 388.89/x
  3. Step 3: Cross multiply
    528.14x = 728.87 × 388.89
  4. Step 4: Simplify right side
    528.14x = 283,448.31
  5. Step 5: Solve for x
    x = 283,448.31/528.14
  6. Step 6: Final answer
    x = 536.69

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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.