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Finding the Fourth Proportional to 642.15, 886.23 and 380.25

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Solution

The fourth proportional to 642.15, 886.23 and 380.25 is: 524.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.15 : 886.23 = 380.25 : x
  2. Step 2: Convert to fraction form
    642.15/886.23 = 380.25/x
  3. Step 3: Cross multiply
    642.15x = 886.23 × 380.25
  4. Step 4: Simplify right side
    642.15x = 336,988.96
  5. Step 5: Solve for x
    x = 336,988.96/642.15
  6. Step 6: Final answer
    x = 524.78

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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.