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Finding the Fourth Proportional to 642.59, 886.78 and 347.86

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Solution

The fourth proportional to 642.59, 886.78 and 347.86 is: 480.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.59 : 886.78 = 347.86 : x
  2. Step 2: Convert to fraction form
    642.59/886.78 = 347.86/x
  3. Step 3: Cross multiply
    642.59x = 886.78 × 347.86
  4. Step 4: Simplify right side
    642.59x = 308,473.21
  5. Step 5: Solve for x
    x = 308,473.21/642.59
  6. Step 6: Final answer
    x = 480.05

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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.