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Finding the Fourth Proportional to 655.25, 904.12 and 389.78

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Solution

The fourth proportional to 655.25, 904.12 and 389.78 is: 537.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    655.25 : 904.12 = 389.78 : x
  2. Step 2: Convert to fraction form
    655.25/904.12 = 389.78/x
  3. Step 3: Cross multiply
    655.25x = 904.12 × 389.78
  4. Step 4: Simplify right side
    655.25x = 352,402.40
  5. Step 5: Solve for x
    x = 352,402.40/655.25
  6. Step 6: Final answer
    x = 537.82

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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.