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Finding the Fourth Proportional to 315.12, 435.12 and 285.84

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Solution

The fourth proportional to 315.12, 435.12 and 285.84 is: 394.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    315.12 : 435.12 = 285.84 : x
  2. Step 2: Convert to fraction form
    315.12/435.12 = 285.84/x
  3. Step 3: Cross multiply
    315.12x = 435.12 × 285.84
  4. Step 4: Simplify right side
    315.12x = 124,374.70
  5. Step 5: Solve for x
    x = 124,374.70/315.12
  6. Step 6: Final answer
    x = 394.69

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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.