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Finding the Fourth Proportional to 643.68, 964.98 and 278.24

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Solution

The fourth proportional to 643.68, 964.98 and 278.24 is: 417.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.68 : 964.98 = 278.24 : x
  2. Step 2: Convert to fraction form
    643.68/964.98 = 278.24/x
  3. Step 3: Cross multiply
    643.68x = 964.98 × 278.24
  4. Step 4: Simplify right side
    643.68x = 268,491.21
  5. Step 5: Solve for x
    x = 268,491.21/643.68
  6. Step 6: Final answer
    x = 417.12

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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.