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Finding the Fourth Proportional to 105.42, 157.88 and 85.08

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Solution

The fourth proportional to 105.42, 157.88 and 85.08 is: 127.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    105.42 : 157.88 = 85.08 : x
  2. Step 2: Convert to fraction form
    105.42/157.88 = 85.08/x
  3. Step 3: Cross multiply
    105.42x = 157.88 × 85.08
  4. Step 4: Simplify right side
    105.42x = 13,432.43
  5. Step 5: Solve for x
    x = 13,432.43/105.42
  6. Step 6: Final answer
    x = 127.42

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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.