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Finding the Fourth Proportional to 128,000.80, 192,001.20 and 81,306.40

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Solution

The fourth proportional to 128,000.80, 192,001.20 and 81,306.40 is: 121,959.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    128,000.80 : 192,001.20 = 81,306.40 : x
  2. Step 2: Convert to fraction form
    128,000.80/192,001.20 = 81,306.40/x
  3. Step 3: Cross multiply
    128,000.80x = 192,001.20 × 81,306.40
  4. Step 4: Simplify right side
    128,000.80x = 15,610,926,367.68
  5. Step 5: Solve for x
    x = 15,610,926,367.68/128,000.80
  6. Step 6: Final answer
    x = 121,959.60

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1.5x scale

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.