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Finding the Fourth Proportional to 71.12, 107.21 and 70.20

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Solution

The fourth proportional to 71.12, 107.21 and 70.20 is: 105.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.12 : 107.21 = 70.20 : x
  2. Step 2: Convert to fraction form
    71.12/107.21 = 70.20/x
  3. Step 3: Cross multiply
    71.12x = 107.21 × 70.20
  4. Step 4: Simplify right side
    71.12x = 7,525.79
  5. Step 5: Solve for x
    x = 7,525.79/71.12
  6. Step 6: Final answer
    x = 105.83

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.