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Finding the Fourth Proportional to 1,380.75, 2,069.67 and 649.71

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Solution

The fourth proportional to 1,380.75, 2,069.67 and 649.71 is: 973.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,380.75 : 2,069.67 = 649.71 : x
  2. Step 2: Convert to fraction form
    1,380.75/2,069.67 = 649.71/x
  3. Step 3: Cross multiply
    1,380.75x = 2,069.67 × 649.71
  4. Step 4: Simplify right side
    1,380.75x = 1,344,685.30
  5. Step 5: Solve for x
    x = 1,344,685.30/1,380.75
  6. Step 6: Final answer
    x = 973.88

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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.