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Finding the Fourth Proportional to 390.30, 538.08 and 270.68

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Solution

The fourth proportional to 390.30, 538.08 and 270.68 is: 373.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.30 : 538.08 = 270.68 : x
  2. Step 2: Convert to fraction form
    390.30/538.08 = 270.68/x
  3. Step 3: Cross multiply
    390.30x = 538.08 × 270.68
  4. Step 4: Simplify right side
    390.30x = 145,644.80
  5. Step 5: Solve for x
    x = 145,644.80/390.30
  6. Step 6: Final answer
    x = 373.16

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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.