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Finding the Fourth Proportional to 65.15, 89.91 and 38.93

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Solution

The fourth proportional to 65.15, 89.91 and 38.93 is: 53.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.15 : 89.91 = 38.93 : x
  2. Step 2: Convert to fraction form
    65.15/89.91 = 38.93/x
  3. Step 3: Cross multiply
    65.15x = 89.91 × 38.93
  4. Step 4: Simplify right side
    65.15x = 3,499.75
  5. Step 5: Solve for x
    x = 3,499.75/65.15
  6. Step 6: Final answer
    x = 53.72

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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.