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Finding the Fourth Proportional to 639.60, 957.57 and 434.57

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Solution

The fourth proportional to 639.60, 957.57 and 434.57 is: 650.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.60 : 957.57 = 434.57 : x
  2. Step 2: Convert to fraction form
    639.60/957.57 = 434.57/x
  3. Step 3: Cross multiply
    639.60x = 957.57 × 434.57
  4. Step 4: Simplify right side
    639.60x = 416,127.22
  5. Step 5: Solve for x
    x = 416,127.22/639.60
  6. Step 6: Final answer
    x = 650.61

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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.