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Finding the Fourth Proportional to 640, 960.18 and 315.28

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Solution

The fourth proportional to 640, 960.18 and 315.28 is: 473.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    640 : 960.18 = 315.28 : x
  2. Step 2: Convert to fraction form
    640/960.18 = 315.28/x
  3. Step 3: Cross multiply
    640x = 960.18 × 315.28
  4. Step 4: Simplify right side
    640x = 302,725.55
  5. Step 5: Solve for x
    x = 302,725.55/640
  6. Step 6: Final answer
    x = 473.01

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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.