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Finding the Fourth Proportional to 61.80, 85.21 and 41.12

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Solution

The fourth proportional to 61.80, 85.21 and 41.12 is: 56.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    61.80 : 85.21 = 41.12 : x
  2. Step 2: Convert to fraction form
    61.80/85.21 = 41.12/x
  3. Step 3: Cross multiply
    61.80x = 85.21 × 41.12
  4. Step 4: Simplify right side
    61.80x = 3,503.95
  5. Step 5: Solve for x
    x = 3,503.95/61.80
  6. Step 6: Final answer
    x = 56.70

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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.