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Finding the Fourth Proportional to 642.64, 886.84 and 347.90

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Solution

The fourth proportional to 642.64, 886.84 and 347.90 is: 480.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.64 : 886.84 = 347.90 : x
  2. Step 2: Convert to fraction form
    642.64/886.84 = 347.90/x
  3. Step 3: Cross multiply
    642.64x = 886.84 × 347.90
  4. Step 4: Simplify right side
    642.64x = 308,532.33
  5. Step 5: Solve for x
    x = 308,532.33/642.64
  6. Step 6: Final answer
    x = 480.10

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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.