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Finding the Fourth Proportional to 85.56, 117.99 and 64.85

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Solution

The fourth proportional to 85.56, 117.99 and 64.85 is: 89.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.56 : 117.99 = 64.85 : x
  2. Step 2: Convert to fraction form
    85.56/117.99 = 64.85/x
  3. Step 3: Cross multiply
    85.56x = 117.99 × 64.85
  4. Step 4: Simplify right side
    85.56x = 7,651.06
  5. Step 5: Solve for x
    x = 7,651.06/85.56
  6. Step 6: Final answer
    x = 89.42

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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.