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Finding the Fourth Proportional to 145.30, 215.26 and 139.90

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Solution

The fourth proportional to 145.30, 215.26 and 139.90 is: 207.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    145.30 : 215.26 = 139.90 : x
  2. Step 2: Convert to fraction form
    145.30/215.26 = 139.90/x
  3. Step 3: Cross multiply
    145.30x = 215.26 × 139.90
  4. Step 4: Simplify right side
    145.30x = 30,114.87
  5. Step 5: Solve for x
    x = 30,114.87/145.30
  6. Step 6: Final answer
    x = 207.26

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Why These Related Problems?

These problems maintain the same ratio (1.48) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.