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Finding the Fourth Proportional to 639.77, 958.60 and 615.78

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Solution

The fourth proportional to 639.77, 958.60 and 615.78 is: 922.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.77 : 958.60 = 615.78 : x
  2. Step 2: Convert to fraction form
    639.77/958.60 = 615.78/x
  3. Step 3: Cross multiply
    639.77x = 958.60 × 615.78
  4. Step 4: Simplify right side
    639.77x = 590,286.71
  5. Step 5: Solve for x
    x = 590,286.71/639.77
  6. Step 6: Final answer
    x = 922.65

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.