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Finding the Fourth Proportional to 638.80, 881.94 and 507.40

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Solution

The fourth proportional to 638.80, 881.94 and 507.40 is: 700.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.80 : 881.94 = 507.40 : x
  2. Step 2: Convert to fraction form
    638.80/881.94 = 507.40/x
  3. Step 3: Cross multiply
    638.80x = 881.94 × 507.40
  4. Step 4: Simplify right side
    638.80x = 447,496.36
  5. Step 5: Solve for x
    x = 447,496.36/638.80
  6. Step 6: Final answer
    x = 700.53

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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.