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Finding the Fourth Proportional to 79.30, 109.20 and 62.92

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Solution

The fourth proportional to 79.30, 109.20 and 62.92 is: 86.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.30 : 109.20 = 62.92 : x
  2. Step 2: Convert to fraction form
    79.30/109.20 = 62.92/x
  3. Step 3: Cross multiply
    79.30x = 109.20 × 62.92
  4. Step 4: Simplify right side
    79.30x = 6,870.86
  5. Step 5: Solve for x
    x = 6,870.86/79.30
  6. Step 6: Final answer
    x = 86.64

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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.