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Finding the Fourth Proportional to 65.71, 90.14 and 64.12

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Solution

The fourth proportional to 65.71, 90.14 and 64.12 is: 87.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    65.71 : 90.14 = 64.12 : x
  2. Step 2: Convert to fraction form
    65.71/90.14 = 64.12/x
  3. Step 3: Cross multiply
    65.71x = 90.14 × 64.12
  4. Step 4: Simplify right side
    65.71x = 5,779.78
  5. Step 5: Solve for x
    x = 5,779.78/65.71
  6. Step 6: Final answer
    x = 87.96

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.