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Finding the Fourth Proportional to 830.87, 1,245.84 and 385.65

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Solution

The fourth proportional to 830.87, 1,245.84 and 385.65 is: 578.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    830.87 : 1,245.84 = 385.65 : x
  2. Step 2: Convert to fraction form
    830.87/1,245.84 = 385.65/x
  3. Step 3: Cross multiply
    830.87x = 1,245.84 × 385.65
  4. Step 4: Simplify right side
    830.87x = 480,451.97
  5. Step 5: Solve for x
    x = 480,451.97/830.87
  6. Step 6: Final answer
    x = 578.26

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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.