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Finding the Fourth Proportional to 312.48, 431.40 and 219.32

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Solution

The fourth proportional to 312.48, 431.40 and 219.32 is: 302.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    312.48 : 431.40 = 219.32 : x
  2. Step 2: Convert to fraction form
    312.48/431.40 = 219.32/x
  3. Step 3: Cross multiply
    312.48x = 431.40 × 219.32
  4. Step 4: Simplify right side
    312.48x = 94,614.65
  5. Step 5: Solve for x
    x = 94,614.65/312.48
  6. Step 6: Final answer
    x = 302.79

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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.