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Finding the Fourth Proportional to 65.95, 91.02 and 39.72

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Solution

The fourth proportional to 65.95, 91.02 and 39.72 is: 54.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.95 : 91.02 = 39.72 : x
  2. Step 2: Convert to fraction form
    65.95/91.02 = 39.72/x
  3. Step 3: Cross multiply
    65.95x = 91.02 × 39.72
  4. Step 4: Simplify right side
    65.95x = 3,615.31
  5. Step 5: Solve for x
    x = 3,615.31/65.95
  6. Step 6: Final answer
    x = 54.82

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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.