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Finding the Fourth Proportional to 655.40, 904.34 and 393.42

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Solution

The fourth proportional to 655.40, 904.34 and 393.42 is: 542.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    655.40 : 904.34 = 393.42 : x
  2. Step 2: Convert to fraction form
    655.40/904.34 = 393.42/x
  3. Step 3: Cross multiply
    655.40x = 904.34 × 393.42
  4. Step 4: Simplify right side
    655.40x = 355,785.44
  5. Step 5: Solve for x
    x = 355,785.44/655.40
  6. Step 6: Final answer
    x = 542.85

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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.