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Finding the Fourth Proportional to 427.10, 640.65 and 319.57

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Solution

The fourth proportional to 427.10, 640.65 and 319.57 is: 479.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.10 : 640.65 = 319.57 : x
  2. Step 2: Convert to fraction form
    427.10/640.65 = 319.57/x
  3. Step 3: Cross multiply
    427.10x = 640.65 × 319.57
  4. Step 4: Simplify right side
    427.10x = 204,729.32
  5. Step 5: Solve for x
    x = 204,729.32/427.10
  6. Step 6: Final answer
    x = 479.35

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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.