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Finding the Fourth Proportional to 61.80, 85.24 and 36.90

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Solution

The fourth proportional to 61.80, 85.24 and 36.90 is: 50.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    61.80 : 85.24 = 36.90 : x
  2. Step 2: Convert to fraction form
    61.80/85.24 = 36.90/x
  3. Step 3: Cross multiply
    61.80x = 85.24 × 36.90
  4. Step 4: Simplify right side
    61.80x = 3,145.36
  5. Step 5: Solve for x
    x = 3,145.36/61.80
  6. Step 6: Final answer
    x = 50.90

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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.