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Finding the Fourth Proportional to 315.96, 435.09 and 309.15

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Solution

The fourth proportional to 315.96, 435.09 and 309.15 is: 425.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    315.96 : 435.09 = 309.15 : x
  2. Step 2: Convert to fraction form
    315.96/435.09 = 309.15/x
  3. Step 3: Cross multiply
    315.96x = 435.09 × 309.15
  4. Step 4: Simplify right side
    315.96x = 134,504.35
  5. Step 5: Solve for x
    x = 134,504.35/315.96
  6. Step 6: Final answer
    x = 425.70

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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.