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Finding the Fourth Proportional to 643.80, 964.98 and 355.80

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Solution

The fourth proportional to 643.80, 964.98 and 355.80 is: 533.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.80 : 964.98 = 355.80 : x
  2. Step 2: Convert to fraction form
    643.80/964.98 = 355.80/x
  3. Step 3: Cross multiply
    643.80x = 964.98 × 355.80
  4. Step 4: Simplify right side
    643.80x = 343,339.88
  5. Step 5: Solve for x
    x = 343,339.88/643.80
  6. Step 6: Final answer
    x = 533.30

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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.