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Finding the Fourth Proportional to 52.80, 79.28 and 39.91

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Solution

The fourth proportional to 52.80, 79.28 and 39.91 is: 59.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    52.80 : 79.28 = 39.91 : x
  2. Step 2: Convert to fraction form
    52.80/79.28 = 39.91/x
  3. Step 3: Cross multiply
    52.80x = 79.28 × 39.91
  4. Step 4: Simplify right side
    52.80x = 3,164.06
  5. Step 5: Solve for x
    x = 3,164.06/52.80
  6. Step 6: Final answer
    x = 59.93

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.