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Finding the Fourth Proportional to 71.29, 106.90 and 53.20

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Solution

The fourth proportional to 71.29, 106.90 and 53.20 is: 79.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.29 : 106.90 = 53.20 : x
  2. Step 2: Convert to fraction form
    71.29/106.90 = 53.20/x
  3. Step 3: Cross multiply
    71.29x = 106.90 × 53.20
  4. Step 4: Simplify right side
    71.29x = 5,687.08
  5. Step 5: Solve for x
    x = 5,687.08/71.29
  6. Step 6: Final answer
    x = 79.77

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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.