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Finding the Fourth Proportional to 640.29, 883.56 and 378.21

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Solution

The fourth proportional to 640.29, 883.56 and 378.21 is: 521.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.29 : 883.56 = 378.21 : x
  2. Step 2: Convert to fraction form
    640.29/883.56 = 378.21/x
  3. Step 3: Cross multiply
    640.29x = 883.56 × 378.21
  4. Step 4: Simplify right side
    640.29x = 334,171.23
  5. Step 5: Solve for x
    x = 334,171.23/640.29
  6. Step 6: Final answer
    x = 521.91

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1.5x scale

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.