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Finding the Fourth Proportional to 830.20, 1,245.45 and 418.30

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Solution

The fourth proportional to 830.20, 1,245.45 and 418.30 is: 627.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    830.20 : 1,245.45 = 418.30 : x
  2. Step 2: Convert to fraction form
    830.20/1,245.45 = 418.30/x
  3. Step 3: Cross multiply
    830.20x = 1,245.45 × 418.30
  4. Step 4: Simplify right side
    830.20x = 520,971.74
  5. Step 5: Solve for x
    x = 520,971.74/830.20
  6. Step 6: Final answer
    x = 627.53

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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.