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Finding the Fourth Proportional to 840.83, 1,261.27 and 285.53

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Solution

The fourth proportional to 840.83, 1,261.27 and 285.53 is: 428.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.83 : 1,261.27 = 285.53 : x
  2. Step 2: Convert to fraction form
    840.83/1,261.27 = 285.53/x
  3. Step 3: Cross multiply
    840.83x = 1,261.27 × 285.53
  4. Step 4: Simplify right side
    840.83x = 360,124.47
  5. Step 5: Solve for x
    x = 360,124.47/840.83
  6. Step 6: Final answer
    x = 428.30

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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.