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Finding the Fourth Proportional to 101.60, 152.55 and 78.80

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Solution

The fourth proportional to 101.60, 152.55 and 78.80 is: 118.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    101.60 : 152.55 = 78.80 : x
  2. Step 2: Convert to fraction form
    101.60/152.55 = 78.80/x
  3. Step 3: Cross multiply
    101.60x = 152.55 × 78.80
  4. Step 4: Simplify right side
    101.60x = 12,020.94
  5. Step 5: Solve for x
    x = 12,020.94/101.60
  6. Step 6: Final answer
    x = 118.32

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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.