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Finding the Fourth Proportional to 77.47, 116.21 and 19.70

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Solution

The fourth proportional to 77.47, 116.21 and 19.70 is: 29.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.47 : 116.21 = 19.70 : x
  2. Step 2: Convert to fraction form
    77.47/116.21 = 19.70/x
  3. Step 3: Cross multiply
    77.47x = 116.21 × 19.70
  4. Step 4: Simplify right side
    77.47x = 2,288.66
  5. Step 5: Solve for x
    x = 2,288.66/77.47
  6. Step 6: Final answer
    x = 29.54

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.