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Finding the Fourth Proportional to 505.45, 757.38 and 285.80

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Solution

The fourth proportional to 505.45, 757.38 and 285.80 is: 428.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    505.45 : 757.38 = 285.80 : x
  2. Step 2: Convert to fraction form
    505.45/757.38 = 285.80/x
  3. Step 3: Cross multiply
    505.45x = 757.38 × 285.80
  4. Step 4: Simplify right side
    505.45x = 216,459.20
  5. Step 5: Solve for x
    x = 216,459.20/505.45
  6. Step 6: Final answer
    x = 428.25

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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.