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Finding the Fourth Proportional to 639.12, 958.28 and 228.18

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Solution

The fourth proportional to 639.12, 958.28 and 228.18 is: 342.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.12 : 958.28 = 228.18 : x
  2. Step 2: Convert to fraction form
    639.12/958.28 = 228.18/x
  3. Step 3: Cross multiply
    639.12x = 958.28 × 228.18
  4. Step 4: Simplify right side
    639.12x = 218,659.19
  5. Step 5: Solve for x
    x = 218,659.19/639.12
  6. Step 6: Final answer
    x = 342.13

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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.