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Finding the Fourth Proportional to 85.75, 128.59 and 60.10

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Solution

The fourth proportional to 85.75, 128.59 and 60.10 is: 90.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.75 : 128.59 = 60.10 : x
  2. Step 2: Convert to fraction form
    85.75/128.59 = 60.10/x
  3. Step 3: Cross multiply
    85.75x = 128.59 × 60.10
  4. Step 4: Simplify right side
    85.75x = 7,728.26
  5. Step 5: Solve for x
    x = 7,728.26/85.75
  6. Step 6: Final answer
    x = 90.13

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.