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Finding the Fourth Proportional to 72.60, 109.47 and 71.70

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Solution

The fourth proportional to 72.60, 109.47 and 71.70 is: 108.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.60 : 109.47 = 71.70 : x
  2. Step 2: Convert to fraction form
    72.60/109.47 = 71.70/x
  3. Step 3: Cross multiply
    72.60x = 109.47 × 71.70
  4. Step 4: Simplify right side
    72.60x = 7,849.00
  5. Step 5: Solve for x
    x = 7,849.00/72.60
  6. Step 6: Final answer
    x = 108.11

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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.