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Finding the Fourth Proportional to 639.60, 881.22 and 528.48

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Solution

The fourth proportional to 639.60, 881.22 and 528.48 is: 728.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.60 : 881.22 = 528.48 : x
  2. Step 2: Convert to fraction form
    639.60/881.22 = 528.48/x
  3. Step 3: Cross multiply
    639.60x = 881.22 × 528.48
  4. Step 4: Simplify right side
    639.60x = 465,707.15
  5. Step 5: Solve for x
    x = 465,707.15/639.60
  6. Step 6: Final answer
    x = 728.12

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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.