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Finding the Fourth Proportional to 390.18, 538.48 and 301.76

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Solution

The fourth proportional to 390.18, 538.48 and 301.76 is: 416.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.18 : 538.48 = 301.76 : x
  2. Step 2: Convert to fraction form
    390.18/538.48 = 301.76/x
  3. Step 3: Cross multiply
    390.18x = 538.48 × 301.76
  4. Step 4: Simplify right side
    390.18x = 162,491.72
  5. Step 5: Solve for x
    x = 162,491.72/390.18
  6. Step 6: Final answer
    x = 416.45

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.