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Finding the Fourth Proportional to 79.85, 110.21 and 47.12

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Solution

The fourth proportional to 79.85, 110.21 and 47.12 is: 65.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.85 : 110.21 = 47.12 : x
  2. Step 2: Convert to fraction form
    79.85/110.21 = 47.12/x
  3. Step 3: Cross multiply
    79.85x = 110.21 × 47.12
  4. Step 4: Simplify right side
    79.85x = 5,192.31
  5. Step 5: Solve for x
    x = 5,192.31/79.85
  6. Step 6: Final answer
    x = 65.02

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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.