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Finding the Fourth Proportional to 642.64, 886.74 and 380.68

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Solution

The fourth proportional to 642.64, 886.74 and 380.68 is: 525.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.64 : 886.74 = 380.68 : x
  2. Step 2: Convert to fraction form
    642.64/886.74 = 380.68/x
  3. Step 3: Cross multiply
    642.64x = 886.74 × 380.68
  4. Step 4: Simplify right side
    642.64x = 337,564.18
  5. Step 5: Solve for x
    x = 337,564.18/642.64
  6. Step 6: Final answer
    x = 525.28

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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.