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Finding the Fourth Proportional to 637.47, 878.85 and 388.80

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Solution

The fourth proportional to 637.47, 878.85 and 388.80 is: 536.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    637.47 : 878.85 = 388.80 : x
  2. Step 2: Convert to fraction form
    637.47/878.85 = 388.80/x
  3. Step 3: Cross multiply
    637.47x = 878.85 × 388.80
  4. Step 4: Simplify right side
    637.47x = 341,696.88
  5. Step 5: Solve for x
    x = 341,696.88/637.47
  6. Step 6: Final answer
    x = 536.02

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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.