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Finding the Fourth Proportional to 640.63, 960.95 and 398.98

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Solution

The fourth proportional to 640.63, 960.95 and 398.98 is: 598.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.63 : 960.95 = 398.98 : x
  2. Step 2: Convert to fraction form
    640.63/960.95 = 398.98/x
  3. Step 3: Cross multiply
    640.63x = 960.95 × 398.98
  4. Step 4: Simplify right side
    640.63x = 383,399.83
  5. Step 5: Solve for x
    x = 383,399.83/640.63
  6. Step 6: Final answer
    x = 598.47

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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.