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Finding the Fourth Proportional to 742.89, 1,114.31 and 280.53

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Solution

The fourth proportional to 742.89, 1,114.31 and 280.53 is: 420.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    742.89 : 1,114.31 = 280.53 : x
  2. Step 2: Convert to fraction form
    742.89/1,114.31 = 280.53/x
  3. Step 3: Cross multiply
    742.89x = 1,114.31 × 280.53
  4. Step 4: Simplify right side
    742.89x = 312,596.51
  5. Step 5: Solve for x
    x = 312,596.51/742.89
  6. Step 6: Final answer
    x = 420.79

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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.