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Finding the Fourth Proportional to 79.47, 109.53 and 65.61

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Solution

The fourth proportional to 79.47, 109.53 and 65.61 is: 90.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.47 : 109.53 = 65.61 : x
  2. Step 2: Convert to fraction form
    79.47/109.53 = 65.61/x
  3. Step 3: Cross multiply
    79.47x = 109.53 × 65.61
  4. Step 4: Simplify right side
    79.47x = 7,186.26
  5. Step 5: Solve for x
    x = 7,186.26/79.47
  6. Step 6: Final answer
    x = 90.43

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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.