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Finding the Fourth Proportional to 528.70, 727.66 and 388.60

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Solution

The fourth proportional to 528.70, 727.66 and 388.60 is: 534.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.70 : 727.66 = 388.60 : x
  2. Step 2: Convert to fraction form
    528.70/727.66 = 388.60/x
  3. Step 3: Cross multiply
    528.70x = 727.66 × 388.60
  4. Step 4: Simplify right side
    528.70x = 282,766.25
  5. Step 5: Solve for x
    x = 282,766.25/528.70
  6. Step 6: Final answer
    x = 534.83

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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.