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Finding the Fourth Proportional to 390.86, 542.18 and 370.10

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Solution

The fourth proportional to 390.86, 542.18 and 370.10 is: 513.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.86 : 542.18 = 370.10 : x
  2. Step 2: Convert to fraction form
    390.86/542.18 = 370.10/x
  3. Step 3: Cross multiply
    390.86x = 542.18 × 370.10
  4. Step 4: Simplify right side
    390.86x = 200,663.10
  5. Step 5: Solve for x
    x = 200,663.10/390.86
  6. Step 6: Final answer
    x = 513.39

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.