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Finding the Fourth Proportional to 77.02, 106.05 and 64.71

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Solution

The fourth proportional to 77.02, 106.05 and 64.71 is: 89.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.02 : 106.05 = 64.71 : x
  2. Step 2: Convert to fraction form
    77.02/106.05 = 64.71/x
  3. Step 3: Cross multiply
    77.02x = 106.05 × 64.71
  4. Step 4: Simplify right side
    77.02x = 6,863.14
  5. Step 5: Solve for x
    x = 6,863.14/77.02
  6. Step 6: Final answer
    x = 89.11

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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.