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Finding the Fourth Proportional to 638.21, 881.48 and 510.90

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Solution

The fourth proportional to 638.21, 881.48 and 510.90 is: 705.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.21 : 881.48 = 510.90 : x
  2. Step 2: Convert to fraction form
    638.21/881.48 = 510.90/x
  3. Step 3: Cross multiply
    638.21x = 881.48 × 510.90
  4. Step 4: Simplify right side
    638.21x = 450,345.58
  5. Step 5: Solve for x
    x = 450,345.58/638.21
  6. Step 6: Final answer
    x = 705.64

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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.