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Finding the Fourth Proportional to 642.89, 964.32 and 210.14

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Solution

The fourth proportional to 642.89, 964.32 and 210.14 is: 315.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.89 : 964.32 = 210.14 : x
  2. Step 2: Convert to fraction form
    642.89/964.32 = 210.14/x
  3. Step 3: Cross multiply
    642.89x = 964.32 × 210.14
  4. Step 4: Simplify right side
    642.89x = 202,642.20
  5. Step 5: Solve for x
    x = 202,642.20/642.89
  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.