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Finding the Fourth Proportional to 64.55, 89.08 and 39.99

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Solution

The fourth proportional to 64.55, 89.08 and 39.99 is: 55.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    64.55 : 89.08 = 39.99 : x
  2. Step 2: Convert to fraction form
    64.55/89.08 = 39.99/x
  3. Step 3: Cross multiply
    64.55x = 89.08 × 39.99
  4. Step 4: Simplify right side
    64.55x = 3,562.31
  5. Step 5: Solve for x
    x = 3,562.31/64.55
  6. Step 6: Final answer
    x = 55.19

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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.