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Finding the Fourth Proportional to 642.80, 963.88 and 354

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Solution

The fourth proportional to 642.80, 963.88 and 354 is: 530.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.80 : 963.88 = 354 : x
  2. Step 2: Convert to fraction form
    642.80/963.88 = 354/x
  3. Step 3: Cross multiply
    642.80x = 963.88 × 354
  4. Step 4: Simplify right side
    642.80x = 341,213.52
  5. Step 5: Solve for x
    x = 341,213.52/642.80
  6. Step 6: Final answer
    x = 530.82

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.