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Finding the Fourth Proportional to 102.40, 152.81 and 84.40

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Solution

The fourth proportional to 102.40, 152.81 and 84.40 is: 125.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    102.40 : 152.81 = 84.40 : x
  2. Step 2: Convert to fraction form
    102.40/152.81 = 84.40/x
  3. Step 3: Cross multiply
    102.40x = 152.81 × 84.40
  4. Step 4: Simplify right side
    102.40x = 12,897.16
  5. Step 5: Solve for x
    x = 12,897.16/102.40
  6. Step 6: Final answer
    x = 125.95

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.