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Finding the Fourth Proportional to 1,220.85, 1,830.99 and 399.09

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Solution

The fourth proportional to 1,220.85, 1,830.99 and 399.09 is: 598.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,220.85 : 1,830.99 = 399.09 : x
  2. Step 2: Convert to fraction form
    1,220.85/1,830.99 = 399.09/x
  3. Step 3: Cross multiply
    1,220.85x = 1,830.99 × 399.09
  4. Step 4: Simplify right side
    1,220.85x = 730,729.80
  5. Step 5: Solve for x
    x = 730,729.80/1,220.85
  6. Step 6: Final answer
    x = 598.54

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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.