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Finding the Fourth Proportional to 101.62, 152.07 and 78.72

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Solution

The fourth proportional to 101.62, 152.07 and 78.72 is: 117.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.62 : 152.07 = 78.72 : x
  2. Step 2: Convert to fraction form
    101.62/152.07 = 78.72/x
  3. Step 3: Cross multiply
    101.62x = 152.07 × 78.72
  4. Step 4: Simplify right side
    101.62x = 11,970.95
  5. Step 5: Solve for x
    x = 11,970.95/101.62
  6. Step 6: Final answer
    x = 117.80

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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.