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Finding the Fourth Proportional to 643, 964.40 and 210.16

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Solution

The fourth proportional to 643, 964.40 and 210.16 is: 315.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    643 : 964.40 = 210.16 : x
  2. Step 2: Convert to fraction form
    643/964.40 = 210.16/x
  3. Step 3: Cross multiply
    643x = 964.40 × 210.16
  4. Step 4: Simplify right side
    643x = 202,678.30
  5. Step 5: Solve for x
    x = 202,678.30/643
  6. Step 6: Final answer
    x = 315.21

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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.