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Finding the Fourth Proportional to 653.85, 902.21 and 391.82

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Solution

The fourth proportional to 653.85, 902.21 and 391.82 is: 540.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.85 : 902.21 = 391.82 : x
  2. Step 2: Convert to fraction form
    653.85/902.21 = 391.82/x
  3. Step 3: Cross multiply
    653.85x = 902.21 × 391.82
  4. Step 4: Simplify right side
    653.85x = 353,497.45
  5. Step 5: Solve for x
    x = 353,497.45/653.85
  6. Step 6: Final answer
    x = 540.64

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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.