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Finding the Fourth Proportional to 76.90, 106.05 and 71.03

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Solution

The fourth proportional to 76.90, 106.05 and 71.03 is: 97.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    76.90 : 106.05 = 71.03 : x
  2. Step 2: Convert to fraction form
    76.90/106.05 = 71.03/x
  3. Step 3: Cross multiply
    76.90x = 106.05 × 71.03
  4. Step 4: Simplify right side
    76.90x = 7,532.20
  5. Step 5: Solve for x
    x = 7,532.20/76.90
  6. Step 6: Final answer
    x = 97.95

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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.