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Finding the Fourth Proportional to 639.21, 957.98 and 268.59

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Solution

The fourth proportional to 639.21, 957.98 and 268.59 is: 402.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.21 : 957.98 = 268.59 : x
  2. Step 2: Convert to fraction form
    639.21/957.98 = 268.59/x
  3. Step 3: Cross multiply
    639.21x = 957.98 × 268.59
  4. Step 4: Simplify right side
    639.21x = 257,303.85
  5. Step 5: Solve for x
    x = 257,303.85/639.21
  6. Step 6: Final answer
    x = 402.53

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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.