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Finding the Fourth Proportional to 65.10, 89.67 and 57.90

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Solution

The fourth proportional to 65.10, 89.67 and 57.90 is: 79.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.10 : 89.67 = 57.90 : x
  2. Step 2: Convert to fraction form
    65.10/89.67 = 57.90/x
  3. Step 3: Cross multiply
    65.10x = 89.67 × 57.90
  4. Step 4: Simplify right side
    65.10x = 5,191.89
  5. Step 5: Solve for x
    x = 5,191.89/65.10
  6. Step 6: Final answer
    x = 79.75

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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.