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Finding the Fourth Proportional to 285.21, 427.50 and 207.75

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Solution

The fourth proportional to 285.21, 427.50 and 207.75 is: 311.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.21 : 427.50 = 207.75 : x
  2. Step 2: Convert to fraction form
    285.21/427.50 = 207.75/x
  3. Step 3: Cross multiply
    285.21x = 427.50 × 207.75
  4. Step 4: Simplify right side
    285.21x = 88,813.13
  5. Step 5: Solve for x
    x = 88,813.13/285.21
  6. Step 6: Final answer
    x = 311.40

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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.