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Finding the Fourth Proportional to 390.08, 585.42 and 143.51

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Solution

The fourth proportional to 390.08, 585.42 and 143.51 is: 215.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.08 : 585.42 = 143.51 : x
  2. Step 2: Convert to fraction form
    390.08/585.42 = 143.51/x
  3. Step 3: Cross multiply
    390.08x = 585.42 × 143.51
  4. Step 4: Simplify right side
    390.08x = 84,015.50
  5. Step 5: Solve for x
    x = 84,015.50/390.08
  6. Step 6: Final answer
    x = 215.38

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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.