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Finding the Fourth Proportional to 642.63, 886.50 and 380.19

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Solution

The fourth proportional to 642.63, 886.50 and 380.19 is: 524.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.63 : 886.50 = 380.19 : x
  2. Step 2: Convert to fraction form
    642.63/886.50 = 380.19/x
  3. Step 3: Cross multiply
    642.63x = 886.50 × 380.19
  4. Step 4: Simplify right side
    642.63x = 337,038.44
  5. Step 5: Solve for x
    x = 337,038.44/642.63
  6. Step 6: Final answer
    x = 524.47

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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.