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Finding the Fourth Proportional to 79.30, 109.53 and 77.62

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Solution

The fourth proportional to 79.30, 109.53 and 77.62 is: 107.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.30 : 109.53 = 77.62 : x
  2. Step 2: Convert to fraction form
    79.30/109.53 = 77.62/x
  3. Step 3: Cross multiply
    79.30x = 109.53 × 77.62
  4. Step 4: Simplify right side
    79.30x = 8,501.72
  5. Step 5: Solve for x
    x = 8,501.72/79.30
  6. Step 6: Final answer
    x = 107.21

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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.