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Finding the Fourth Proportional to 640.56, 883.86 and 388.50

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Solution

The fourth proportional to 640.56, 883.86 and 388.50 is: 536.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.56 : 883.86 = 388.50 : x
  2. Step 2: Convert to fraction form
    640.56/883.86 = 388.50/x
  3. Step 3: Cross multiply
    640.56x = 883.86 × 388.50
  4. Step 4: Simplify right side
    640.56x = 343,379.61
  5. Step 5: Solve for x
    x = 343,379.61/640.56
  6. Step 6: Final answer
    x = 536.06

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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.