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Finding the Fourth Proportional to 642.38, 886.16 and 380.30

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Solution

The fourth proportional to 642.38, 886.16 and 380.30 is: 524.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.38 : 886.16 = 380.30 : x
  2. Step 2: Convert to fraction form
    642.38/886.16 = 380.30/x
  3. Step 3: Cross multiply
    642.38x = 886.16 × 380.30
  4. Step 4: Simplify right side
    642.38x = 337,006.65
  5. Step 5: Solve for x
    x = 337,006.65/642.38
  6. Step 6: Final answer
    x = 524.62

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1.5x scale

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.