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Finding the Fourth Proportional to 64.77, 89.35 and 40.20

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Solution

The fourth proportional to 64.77, 89.35 and 40.20 is: 55.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    64.77 : 89.35 = 40.20 : x
  2. Step 2: Convert to fraction form
    64.77/89.35 = 40.20/x
  3. Step 3: Cross multiply
    64.77x = 89.35 × 40.20
  4. Step 4: Simplify right side
    64.77x = 3,591.87
  5. Step 5: Solve for x
    x = 3,591.87/64.77
  6. Step 6: Final answer
    x = 55.46

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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.