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Finding the Fourth Proportional to 528.16, 728.34 and 388.38

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Solution

The fourth proportional to 528.16, 728.34 and 388.38 is: 535.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.16 : 728.34 = 388.38 : x
  2. Step 2: Convert to fraction form
    528.16/728.34 = 388.38/x
  3. Step 3: Cross multiply
    528.16x = 728.34 × 388.38
  4. Step 4: Simplify right side
    528.16x = 282,872.69
  5. Step 5: Solve for x
    x = 282,872.69/528.16
  6. Step 6: Final answer
    x = 535.58

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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.