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Finding the Fourth Proportional to 85.74, 118.29 and 72.60

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Solution

The fourth proportional to 85.74, 118.29 and 72.60 is: 100.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.74 : 118.29 = 72.60 : x
  2. Step 2: Convert to fraction form
    85.74/118.29 = 72.60/x
  3. Step 3: Cross multiply
    85.74x = 118.29 × 72.60
  4. Step 4: Simplify right side
    85.74x = 8,587.85
  5. Step 5: Solve for x
    x = 8,587.85/85.74
  6. Step 6: Final answer
    x = 100.16

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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.