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Finding the Fourth Proportional to 72.66, 109.57 and 71.30

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Solution

The fourth proportional to 72.66, 109.57 and 71.30 is: 107.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.66 : 109.57 = 71.30 : x
  2. Step 2: Convert to fraction form
    72.66/109.57 = 71.30/x
  3. Step 3: Cross multiply
    72.66x = 109.57 × 71.30
  4. Step 4: Simplify right side
    72.66x = 7,811.88
  5. Step 5: Solve for x
    x = 7,811.88/72.66
  6. Step 6: Final answer
    x = 107.51

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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.