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Finding the Fourth Proportional to 642.65, 886.86 and 347.92

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Solution

The fourth proportional to 642.65, 886.86 and 347.92 is: 480.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.65 : 886.86 = 347.92 : x
  2. Step 2: Convert to fraction form
    642.65/886.86 = 347.92/x
  3. Step 3: Cross multiply
    642.65x = 886.86 × 347.92
  4. Step 4: Simplify right side
    642.65x = 308,557.59
  5. Step 5: Solve for x
    x = 308,557.59/642.65
  6. Step 6: Final answer
    x = 480.13

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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.