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Finding the Fourth Proportional to 79.23, 109.47 and 71.79

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Solution

The fourth proportional to 79.23, 109.47 and 71.79 is: 99.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.23 : 109.47 = 71.79 : x
  2. Step 2: Convert to fraction form
    79.23/109.47 = 71.79/x
  3. Step 3: Cross multiply
    79.23x = 109.47 × 71.79
  4. Step 4: Simplify right side
    79.23x = 7,858.85
  5. Step 5: Solve for x
    x = 7,858.85/79.23
  6. Step 6: Final answer
    x = 99.19

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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.