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Finding the Fourth Proportional to 839.80, 1,260.46 and 429.22

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Solution

The fourth proportional to 839.80, 1,260.46 and 429.22 is: 644.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    839.80 : 1,260.46 = 429.22 : x
  2. Step 2: Convert to fraction form
    839.80/1,260.46 = 429.22/x
  3. Step 3: Cross multiply
    839.80x = 1,260.46 × 429.22
  4. Step 4: Simplify right side
    839.80x = 541,008.34
  5. Step 5: Solve for x
    x = 541,008.34/839.80
  6. Step 6: Final answer
    x = 644.21

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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.