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Finding the Fourth Proportional to 643.51, 964.90 and 253.05

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Solution

The fourth proportional to 643.51, 964.90 and 253.05 is: 379.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.51 : 964.90 = 253.05 : x
  2. Step 2: Convert to fraction form
    643.51/964.90 = 253.05/x
  3. Step 3: Cross multiply
    643.51x = 964.90 × 253.05
  4. Step 4: Simplify right side
    643.51x = 244,171.07
  5. Step 5: Solve for x
    x = 244,171.07/643.51
  6. Step 6: Final answer
    x = 379.44

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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.