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Finding the Fourth Proportional to 1,819.80, 2,729.70 and 780.30

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Solution

The fourth proportional to 1,819.80, 2,729.70 and 780.30 is: 1,170.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,819.80 : 2,729.70 = 780.30 : x
  2. Step 2: Convert to fraction form
    1,819.80/2,729.70 = 780.30/x
  3. Step 3: Cross multiply
    1,819.80x = 2,729.70 × 780.30
  4. Step 4: Simplify right side
    1,819.80x = 2,129,984.91
  5. Step 5: Solve for x
    x = 2,129,984.91/1,819.80
  6. Step 6: Final answer
    x = 1,170.45

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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.