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Finding the Fourth Proportional to 639, 958.31 and 228.08

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Solution

The fourth proportional to 639, 958.31 and 228.08 is: 342.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    639 : 958.31 = 228.08 : x
  2. Step 2: Convert to fraction form
    639/958.31 = 228.08/x
  3. Step 3: Cross multiply
    639x = 958.31 × 228.08
  4. Step 4: Simplify right side
    639x = 218,570.20
  5. Step 5: Solve for x
    x = 218,570.20/639
  6. Step 6: Final answer
    x = 342.05

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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.