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Finding the Fourth Proportional to 148.40, 204.69 and 128.74

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Solution

The fourth proportional to 148.40, 204.69 and 128.74 is: 177.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    148.40 : 204.69 = 128.74 : x
  2. Step 2: Convert to fraction form
    148.40/204.69 = 128.74/x
  3. Step 3: Cross multiply
    148.40x = 204.69 × 128.74
  4. Step 4: Simplify right side
    148.40x = 26,352.15
  5. Step 5: Solve for x
    x = 26,352.15/148.40
  6. Step 6: Final answer
    x = 177.58

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.