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Finding the Fourth Proportional to 415.85, 623.20 and 328.80

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Solution

The fourth proportional to 415.85, 623.20 and 328.80 is: 492.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    415.85 : 623.20 = 328.80 : x
  2. Step 2: Convert to fraction form
    415.85/623.20 = 328.80/x
  3. Step 3: Cross multiply
    415.85x = 623.20 × 328.80
  4. Step 4: Simplify right side
    415.85x = 204,908.16
  5. Step 5: Solve for x
    x = 204,908.16/415.85
  6. Step 6: Final answer
    x = 492.75

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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.