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Finding the Fourth Proportional to 840.18, 1,260.34 and 407

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Solution

The fourth proportional to 840.18, 1,260.34 and 407 is: 610.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.18 : 1,260.34 = 407 : x
  2. Step 2: Convert to fraction form
    840.18/1,260.34 = 407/x
  3. Step 3: Cross multiply
    840.18x = 1,260.34 × 407
  4. Step 4: Simplify right side
    840.18x = 512,958.38
  5. Step 5: Solve for x
    x = 512,958.38/840.18
  6. Step 6: Final answer
    x = 610.53

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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.