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Finding the Fourth Proportional to 642.90, 887.09 and 377.35

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Solution

The fourth proportional to 642.90, 887.09 and 377.35 is: 520.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.90 : 887.09 = 377.35 : x
  2. Step 2: Convert to fraction form
    642.90/887.09 = 377.35/x
  3. Step 3: Cross multiply
    642.90x = 887.09 × 377.35
  4. Step 4: Simplify right side
    642.90x = 334,743.41
  5. Step 5: Solve for x
    x = 334,743.41/642.90
  6. Step 6: Final answer
    x = 520.68

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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.