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Finding the Fourth Proportional to 640.17, 959.32 and 315.77

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Solution

The fourth proportional to 640.17, 959.32 and 315.77 is: 473.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.17 : 959.32 = 315.77 : x
  2. Step 2: Convert to fraction form
    640.17/959.32 = 315.77/x
  3. Step 3: Cross multiply
    640.17x = 959.32 × 315.77
  4. Step 4: Simplify right side
    640.17x = 302,920.07
  5. Step 5: Solve for x
    x = 302,920.07/640.17
  6. Step 6: Final answer
    x = 473.19

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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.