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Finding the Fourth Proportional to 319.08, 439.74 and 309.72

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Solution

The fourth proportional to 319.08, 439.74 and 309.72 is: 426.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.08 : 439.74 = 309.72 : x
  2. Step 2: Convert to fraction form
    319.08/439.74 = 309.72/x
  3. Step 3: Cross multiply
    319.08x = 439.74 × 309.72
  4. Step 4: Simplify right side
    319.08x = 136,196.27
  5. Step 5: Solve for x
    x = 136,196.27/319.08
  6. Step 6: Final answer
    x = 426.84

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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.