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Finding the Fourth Proportional to 643, 964.50 and 187

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Solution

The fourth proportional to 643, 964.50 and 187 is: 280.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    643 : 964.50 = 187 : x
  2. Step 2: Convert to fraction form
    643/964.50 = 187/x
  3. Step 3: Cross multiply
    643x = 964.50 × 187
  4. Step 4: Simplify right side
    643x = 180,361.50
  5. Step 5: Solve for x
    x = 180,361.50/643
  6. Step 6: Final answer
    x = 280.50

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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.