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Finding the Fourth Proportional to 639.81, 959.68 and 228.93

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Solution

The fourth proportional to 639.81, 959.68 and 228.93 is: 343.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.81 : 959.68 = 228.93 : x
  2. Step 2: Convert to fraction form
    639.81/959.68 = 228.93/x
  3. Step 3: Cross multiply
    639.81x = 959.68 × 228.93
  4. Step 4: Simplify right side
    639.81x = 219,696.57
  5. Step 5: Solve for x
    x = 219,696.57/639.81
  6. Step 6: Final answer
    x = 343.38

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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.