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Finding the Fourth Proportional to 840.25, 1,260.64 and 378.43

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Solution

The fourth proportional to 840.25, 1,260.64 and 378.43 is: 567.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.25 : 1,260.64 = 378.43 : x
  2. Step 2: Convert to fraction form
    840.25/1,260.64 = 378.43/x
  3. Step 3: Cross multiply
    840.25x = 1,260.64 × 378.43
  4. Step 4: Simplify right side
    840.25x = 477,064.00
  5. Step 5: Solve for x
    x = 477,064.00/840.25
  6. Step 6: Final answer
    x = 567.76

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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.