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Finding the Fourth Proportional to 840.09, 1,260.21 and 346.40

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Solution

The fourth proportional to 840.09, 1,260.21 and 346.40 is: 519.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.09 : 1,260.21 = 346.40 : x
  2. Step 2: Convert to fraction form
    840.09/1,260.21 = 346.40/x
  3. Step 3: Cross multiply
    840.09x = 1,260.21 × 346.40
  4. Step 4: Simplify right side
    840.09x = 436,530.44
  5. Step 5: Solve for x
    x = 436,530.44/840.09
  6. Step 6: Final answer
    x = 519.62

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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.