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Finding the Fourth Proportional to 642.57, 886.85 and 380.67

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Solution

The fourth proportional to 642.57, 886.85 and 380.67 is: 525.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.57 : 886.85 = 380.67 : x
  2. Step 2: Convert to fraction form
    642.57/886.85 = 380.67/x
  3. Step 3: Cross multiply
    642.57x = 886.85 × 380.67
  4. Step 4: Simplify right side
    642.57x = 337,597.19
  5. Step 5: Solve for x
    x = 337,597.19/642.57
  6. Step 6: Final answer
    x = 525.39

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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.