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Finding the Fourth Proportional to 387.08, 579.40 and 328.76

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Solution

The fourth proportional to 387.08, 579.40 and 328.76 is: 492.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.08 : 579.40 = 328.76 : x
  2. Step 2: Convert to fraction form
    387.08/579.40 = 328.76/x
  3. Step 3: Cross multiply
    387.08x = 579.40 × 328.76
  4. Step 4: Simplify right side
    387.08x = 190,483.54
  5. Step 5: Solve for x
    x = 190,483.54/387.08
  6. Step 6: Final answer
    x = 492.10

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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.