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Finding the Fourth Proportional to 390.23, 538.29 and 250.30

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Solution

The fourth proportional to 390.23, 538.29 and 250.30 is: 345.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.23 : 538.29 = 250.30 : x
  2. Step 2: Convert to fraction form
    390.23/538.29 = 250.30/x
  3. Step 3: Cross multiply
    390.23x = 538.29 × 250.30
  4. Step 4: Simplify right side
    390.23x = 134,730.04
  5. Step 5: Solve for x
    x = 134,730.04/390.23
  6. Step 6: Final answer
    x = 345.26

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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.