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Finding the Fourth Proportional to 830.00, 1,245.00 and 391.10

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Solution

The fourth proportional to 830.00, 1,245.00 and 391.10 is: 586.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    830.00 : 1,245.00 = 391.10 : x
  2. Step 2: Convert to fraction form
    830.00/1,245.00 = 391.10/x
  3. Step 3: Cross multiply
    830.00x = 1,245.00 × 391.10
  4. Step 4: Simplify right side
    830.00x = 486,921.95
  5. Step 5: Solve for x
    x = 486,921.95/830.00
  6. Step 6: Final answer
    x = 586.66

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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.