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Finding the Fourth Proportional to 505.20, 697.56 and 387.48

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Solution

The fourth proportional to 505.20, 697.56 and 387.48 is: 535.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.20 : 697.56 = 387.48 : x
  2. Step 2: Convert to fraction form
    505.20/697.56 = 387.48/x
  3. Step 3: Cross multiply
    505.20x = 697.56 × 387.48
  4. Step 4: Simplify right side
    505.20x = 270,290.55
  5. Step 5: Solve for x
    x = 270,290.55/505.20
  6. Step 6: Final answer
    x = 535.02

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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.