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Finding the Fourth Proportional to 420.25, 579.90 and 233.75

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Solution

The fourth proportional to 420.25, 579.90 and 233.75 is: 322.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.25 : 579.90 = 233.75 : x
  2. Step 2: Convert to fraction form
    420.25/579.90 = 233.75/x
  3. Step 3: Cross multiply
    420.25x = 579.90 × 233.75
  4. Step 4: Simplify right side
    420.25x = 135,551.63
  5. Step 5: Solve for x
    x = 135,551.63/420.25
  6. Step 6: Final answer
    x = 322.55

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.