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Finding the Fourth Proportional to 85.35, 117.79 and 64.59

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Solution

The fourth proportional to 85.35, 117.79 and 64.59 is: 89.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.35 : 117.79 = 64.59 : x
  2. Step 2: Convert to fraction form
    85.35/117.79 = 64.59/x
  3. Step 3: Cross multiply
    85.35x = 117.79 × 64.59
  4. Step 4: Simplify right side
    85.35x = 7,608.06
  5. Step 5: Solve for x
    x = 7,608.06/85.35
  6. Step 6: Final answer
    x = 89.14

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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.