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Finding the Fourth Proportional to 79.23, 109.22 and 65.39

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Solution

The fourth proportional to 79.23, 109.22 and 65.39 is: 90.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.23 : 109.22 = 65.39 : x
  2. Step 2: Convert to fraction form
    79.23/109.22 = 65.39/x
  3. Step 3: Cross multiply
    79.23x = 109.22 × 65.39
  4. Step 4: Simplify right side
    79.23x = 7,141.02
  5. Step 5: Solve for x
    x = 7,141.02/79.23
  6. Step 6: Final answer
    x = 90.13

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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.