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Finding the Fourth Proportional to 47.70, 65.79 and 39.51

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Solution

The fourth proportional to 47.70, 65.79 and 39.51 is: 54.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    47.70 : 65.79 = 39.51 : x
  2. Step 2: Convert to fraction form
    47.70/65.79 = 39.51/x
  3. Step 3: Cross multiply
    47.70x = 65.79 × 39.51
  4. Step 4: Simplify right side
    47.70x = 2,599.36
  5. Step 5: Solve for x
    x = 2,599.36/47.70
  6. Step 6: Final answer
    x = 54.49

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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.