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Finding the Fourth Proportional to 528.07, 728.42 and 388.55

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Solution

The fourth proportional to 528.07, 728.42 and 388.55 is: 535.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.07 : 728.42 = 388.55 : x
  2. Step 2: Convert to fraction form
    528.07/728.42 = 388.55/x
  3. Step 3: Cross multiply
    528.07x = 728.42 × 388.55
  4. Step 4: Simplify right side
    528.07x = 283,024.46
  5. Step 5: Solve for x
    x = 283,024.46/528.07
  6. Step 6: Final answer
    x = 535.96

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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.