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Finding the Fourth Proportional to 610.70, 842.88 and 389.60

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Solution

The fourth proportional to 610.70, 842.88 and 389.60 is: 537.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    610.70 : 842.88 = 389.60 : x
  2. Step 2: Convert to fraction form
    610.70/842.88 = 389.60/x
  3. Step 3: Cross multiply
    610.70x = 842.88 × 389.60
  4. Step 4: Simplify right side
    610.70x = 328,381.83
  5. Step 5: Solve for x
    x = 328,381.83/610.70
  6. Step 6: Final answer
    x = 537.72

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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.