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Finding the Fourth Proportional to 79.19, 109.31 and 51.58

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Solution

The fourth proportional to 79.19, 109.31 and 51.58 is: 71.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.19 : 109.31 = 51.58 : x
  2. Step 2: Convert to fraction form
    79.19/109.31 = 51.58/x
  3. Step 3: Cross multiply
    79.19x = 109.31 × 51.58
  4. Step 4: Simplify right side
    79.19x = 5,638.21
  5. Step 5: Solve for x
    x = 5,638.21/79.19
  6. Step 6: Final answer
    x = 71.20

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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.