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Finding the Fourth Proportional to 65.78, 98.33 and 57.30

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Solution

The fourth proportional to 65.78, 98.33 and 57.30 is: 85.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.78 : 98.33 = 57.30 : x
  2. Step 2: Convert to fraction form
    65.78/98.33 = 57.30/x
  3. Step 3: Cross multiply
    65.78x = 98.33 × 57.30
  4. Step 4: Simplify right side
    65.78x = 5,634.31
  5. Step 5: Solve for x
    x = 5,634.31/65.78
  6. Step 6: Final answer
    x = 85.65

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.