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Finding the Fourth Proportional to 640.08, 959.55 and 310.85

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Solution

The fourth proportional to 640.08, 959.55 and 310.85 is: 465.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.08 : 959.55 = 310.85 : x
  2. Step 2: Convert to fraction form
    640.08/959.55 = 310.85/x
  3. Step 3: Cross multiply
    640.08x = 959.55 × 310.85
  4. Step 4: Simplify right side
    640.08x = 298,271.32
  5. Step 5: Solve for x
    x = 298,271.32/640.08
  6. Step 6: Final answer
    x = 465.99

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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.