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Finding the Fourth Proportional to 125.40, 187.98 and 79.68

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Solution

The fourth proportional to 125.40, 187.98 and 79.68 is: 119.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    125.40 : 187.98 = 79.68 : x
  2. Step 2: Convert to fraction form
    125.40/187.98 = 79.68/x
  3. Step 3: Cross multiply
    125.40x = 187.98 × 79.68
  4. Step 4: Simplify right side
    125.40x = 14,978.25
  5. Step 5: Solve for x
    x = 14,978.25/125.40
  6. Step 6: Final answer
    x = 119.44

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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.