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Finding the Fourth Proportional to 85.50, 117.99 and 52.80

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Solution

The fourth proportional to 85.50, 117.99 and 52.80 is: 72.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.50 : 117.99 = 52.80 : x
  2. Step 2: Convert to fraction form
    85.50/117.99 = 52.80/x
  3. Step 3: Cross multiply
    85.50x = 117.99 × 52.80
  4. Step 4: Simplify right side
    85.50x = 6,229.87
  5. Step 5: Solve for x
    x = 6,229.87/85.50
  6. Step 6: Final answer
    x = 72.86

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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.