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Finding the Fourth Proportional to 56.75, 78.33 and 39.30

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Solution

The fourth proportional to 56.75, 78.33 and 39.30 is: 54.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    56.75 : 78.33 = 39.30 : x
  2. Step 2: Convert to fraction form
    56.75/78.33 = 39.30/x
  3. Step 3: Cross multiply
    56.75x = 78.33 × 39.30
  4. Step 4: Simplify right side
    56.75x = 3,078.37
  5. Step 5: Solve for x
    x = 3,078.37/56.75
  6. Step 6: Final answer
    x = 54.24

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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.