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Finding the Fourth Proportional to 640.45, 883.47 and 378.42

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Solution

The fourth proportional to 640.45, 883.47 and 378.42 is: 522.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.45 : 883.47 = 378.42 : x
  2. Step 2: Convert to fraction form
    640.45/883.47 = 378.42/x
  3. Step 3: Cross multiply
    640.45x = 883.47 × 378.42
  4. Step 4: Simplify right side
    640.45x = 334,322.72
  5. Step 5: Solve for x
    x = 334,322.72/640.45
  6. Step 6: Final answer
    x = 522.01

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.