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Finding the Fourth Proportional to 639.59, 959.40 and 228.65

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Solution

The fourth proportional to 639.59, 959.40 and 228.65 is: 342.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.59 : 959.40 = 228.65 : x
  2. Step 2: Convert to fraction form
    639.59/959.40 = 228.65/x
  3. Step 3: Cross multiply
    639.59x = 959.40 × 228.65
  4. Step 4: Simplify right side
    639.59x = 219,362.01
  5. Step 5: Solve for x
    x = 219,362.01/639.59
  6. Step 6: Final answer
    x = 342.98

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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.